Difference between revisions of "Linux Router with VPN on a Raspberry Pi"

From Alpine Linux
Jump to: navigation, search
(/etc/sysctl.d/local.conf: Removed. Many of the keys are set by 00-alpine.conf, others are default in the Linux kernel or have been removed entirely from the kernel (unknown key).)
(Mention dhcpcd)
 
(20 intermediate revisions by 3 users not shown)
Line 1: Line 1:
[[Category:Networking]]
+
{{TOC right}}
 +
 
 
= Rationale =
 
= Rationale =
  
Line 27: Line 28:
  
 
The modem I am using is a [http://www.cisco.com/c/en/us/products/routers/877-integrated-services-router-isr/index.html Cisco 877 Integrated Services Router]. It has no web interface and is controlled over SSH. More information can be found [[Configuring a Cisco 877 in full bridge mode]].
 
The modem I am using is a [http://www.cisco.com/c/en/us/products/routers/877-integrated-services-router-isr/index.html Cisco 877 Integrated Services Router]. It has no web interface and is controlled over SSH. More information can be found [[Configuring a Cisco 877 in full bridge mode]].
 
= Configuring PPP =
 
Next up we need to configure our router to be able to dial a PPP connection with our modem.
 
 
{{cmd|apk add ppp-pppoe}}
 
 
Check that the interface between your router and modem is eth1, or change it. Enter your credentials at the bottom of the file or use /etc/ppp/chap-secrets
 
 
== /etc/ppp/peers/yourISP ==
 
<pre>#
 
# PPP Configuration file
 
#
 
 
nolog
 
 
# Try to get the IP address from the ISP
 
noipdefault
 
 
# Try to get the name server addresses from the ISP
 
usepeerdns
 
 
# Use this connection as the default route.
 
defaultroute
 
defaultroute-metric 300
 
 
# detatch after ppp0 interface is created
 
updetach
 
 
# Replace previous default route
 
# This requires a special patch to ppp
 
# https://sources.debian.net/src/ppp/2.4.7-1%2B1~exp1/debian/patches/cifdefroute.dif/
 
# replacedefaultroute
 
 
# rp-pppoe plug-in makes PPPoE connection so rp-pppoe package is not needed
 
# Possibly, you may need to change interface according your configuration
 
plugin rp-pppoe.so eth1
 
 
# Uncomment if you need on-demand connection
 
#demand
 
 
# Disconnect after 300 seconds (5 minutes) of idle time.
 
#idle 300
 
 
# Hide password from log entries
 
hide-password
 
 
# Send echo requests
 
lcp-echo-interval 20
 
lcp-echo-failure 3
 
 
# Do not authenticate ISP peer
 
noauth
 
 
# Control connection consistency
 
persist
 
maxfail 0
 
 
# Control MTU size if your ISP does not force it
 
#mtu 1492
 
 
user "username@yourISP.tld"
 
 
# Compression
 
bsdcomp 15
 
deflate 15</pre>
 
 
== /etc/ppp/chap-secrets ==
 
Enter in your login credentials
 
 
<pre># Secrets for authentication using CHAP
 
# client server secret IP addresses
 
"username@yourISP.tld"         * "<your password>"</pre>
 
 
== /etc/modules ==
 
Update modules to include pppoe:
 
<pre>pppoe</pre>
 
  
 
= Network =
 
= Network =
Line 140: Line 65:
 
   address 192.168.1.1
 
   address 192.168.1.1
 
   netmask 255.255.255.0
 
   netmask 255.255.255.0
   broadcast 192.168.1.255
+
   broadcast 192.168.1.255</pre>
  
# External Interface - facing Modem
+
 
 +
=== PPP ===
 +
Next up we need to configure our router to be able to dial a PPP connection with our modem.
 +
 
 +
If your ISP uses [https://en.wikipedia.org/wiki/Point-to-Point_Protocol PPP] you may need to configure it. See [[PPP]].
 +
 
 +
You will want to make sure you set your WAN interface, in this example we used eth1.
 +
 
 +
<pre># External Interface - facing Modem
 
allow-hotplug eth1
 
allow-hotplug eth1
 
auto eth1
 
auto eth1
Line 158: Line 91:
 
   provider yourISP</pre>
 
   provider yourISP</pre>
  
== Basic IPtables firewall with routing ==
+
=== IPoE ===
This demonstrates how to set up basic routing with a permissive outgoing firewall. Incoming packets are blocked. The rest is commented in the rule set.
+
Alternatively it's quite common for ISPs to use [https://en.wikipedia.org/wiki/IPoE IPoE]. IPoE is much simpler and only runs DHCP on the external interface. It should look something like:
 +
 
 +
<pre># External interface to ISP
 +
allow-hotplug eth1
 +
auto eth1
 +
iface eth1 inet dhcp
  
First install iptables:
+
iface eth1 inet static
 +
    address 192.168.0.2
 +
    netmask 255.255.255.252
 +
    broadcast 192.168.0.3
  
{{cmd|apk add iptables ip6tables}}
+
iface eth1 inet6 manual</pre>
  
<pre>#########################################################################
+
==== DHCP from ISP ====
# Basic iptables IPv4 routing rule set
 
#
 
# 192.168.1.0/24 routed directly to PPP0 via NAT
 
#
 
#########################################################################
 
  
#
+
Above we set DHCP and we set a static IP. The purpose of this is so we can still forward packets through to the modem to be able to access the web interface or ssh.
# Mangle Table
 
# We leave this empty for the moment.
 
#
 
*mangle
 
:PREROUTING ACCEPT [0:0]
 
:INPUT ACCEPT [0:0]
 
:FORWARD ACCEPT [0:0]
 
:OUTPUT ACCEPT [0:0]
 
:POSTROUTING ACCEPT [0:0]
 
COMMIT
 
  
#
+
We do still need DHCP to get an IP address form our ISP though. I like to use dhcpcd instead of udhcp (the default in Alpine Linux), because it allows for [https://en.wikipedia.org/wiki/Prefix_delegation Prefix Delegation], which is used in IPv6 networks.
# Filter Table
+
 
# This is where we decide to ACCEPT, DROP or REJECT things
+
My /etc/dhcpcd.conf looks like this:
#
 
*filter
 
:INPUT DROP [0:0]
 
:FORWARD DROP [0:0]
 
:OUTPUT ACCEPT [0:0]
 
*filter
 
  
# Create rule chain per input interface for forwarding packets
+
<pre># Enable extra debugging
:FWD_ETH0 - [0:0]
+
# debug
:FWD_ETH1 - [0:0]
+
# logfile /var/log/dhcpcd.log
:FWD_PPP0 - [0:0]
 
  
# Create rule chain per input interface for input packets (for host itself)
+
# Allow users of this group to interact with dhcpcd via the control
:IN_ETH0 - [0:0]
+
# socket.
:IN_ETH1 - [0:0]
+
#controlgroup wheel
:IN_PPP0 - [0:0]
 
  
# Create a log drop chain
+
# Inform the DHCP server of our hostname for DDNS.
:LOG_DROP - [0:0]
+
hostname gateway
  
# Pass input packet to corresponding rule chain
+
# Use the hardware address of the interface for the Client ID.
-A INPUT -i lo -j ACCEPT
+
# clientid
-A INPUT -i eth0 -j IN_ETH0
+
# or
-A INPUT -i eth1 -j IN_ETH1
+
# Use the same DUID + IAID as set in DHCPv6 for DHCPv4 ClientID as
-A INPUT -i ppp0 -j IN_PPP0
+
# per RFC4361. Some non-RFC compliant DHCP servers do not reply with
 +
# this set. In this case, comment out duid and enable clientid above.
 +
duid
  
# Pass forwarded packet to corresponding rule chain
+
# Persist interface configuration when dhcpcd exits.
-A FORWARD -i eth0 -j FWD_ETH0
+
persistent
-A FORWARD -i eth1 -j FWD_ETH1
 
-A FORWARD -i ppp0 -j FWD_PPP0
 
  
# Forward LAN traffic out
+
# Rapid commit support.
-A FWD_ETH0 -s 192.168.1.0/24 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
+
# Safe to enable by default because it requires the equivalent option
 +
# set on the server to actually work.
 +
option rapid_commit
  
# Forward SSH packets from network to modem
+
# A list of options to request from the DHCP server.
-A FWD_ETH1 -s 192.168.0.0/30 -d 192.168.1.0/24 -p tcp -m tcp --sport 22 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
+
option domain_name_servers, domain_name, domain_search, host_name
 +
option classless_static_routes
  
# Forward HTTP to modem's webserver
+
# Most distributions have NTP support.
-A FWD_ETH1 -s 192.168.0.0/30 -d 192.168.1.0/24 -p tcp -m tcp --sport 80 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
+
option ntp_servers
  
# Forward traffic to ISP
+
# Respect the network MTU.
-A FWD_PPP0 -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT
+
# Some interface drivers reset when changing the MTU so disabled by
 +
# default.
 +
#option interface_mtu 1586
  
# SSH to Router
+
# A ServerID is required by RFC2131.
-A IN_ETH0 -s 192.168.1.0/24 -p tcp -m tcp --dport 22 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
+
require dhcp_server_identifier
  
# DNS to Router
+
# Generate Stable Private IPv6 Addresses instead of hardware based
-A IN_ETH0 -s 192.168.1.0/24 -p tcp -m tcp --dport 1812 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
+
# ones
 +
slaac private
  
# FreeRadius Client (eg a UniFi AP)
+
# A hook script is provided to lookup the hostname if not set by the
-A IN_ETH0 -s 192.168.1.0/24 -p udp -m udp --dport 1812 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
+
# DHCP server, but it should not be run by default.
 +
nohook lookup-hostname
  
# NTP to Router
+
# Disable solicitations on all interfaces
-A IN_ETH0 -s 192.168.1.0/24 -p udp -m udp --dport 123 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
+
noipv6rs
  
# Accept traffic
+
# Wait for IP before forking to background
-A IN_ETH0 -s 192.168.1.0/24 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
+
waitip 6
  
# SSH To Modem from Router
+
# Don't touch DNS
-A IN_ETH1 -s 192.168.0.1/32 -d 192.168.0.0/30 -p tcp -m tcp --sport 22 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
+
nohook resolv.conf
  
# HTTP to modem
+
allowinterfaces eth1 eth0.2
-A IN_ETH1 -s 192.168.0.1/32 -d 192.168.0.0/30 -p tcp -m tcp --sport 80 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
+
# Use the interface connected to WAN
 +
interface eth1
 +
    waitip 4
 +
    noipv4ll
 +
    ipv6rs # enable routing solicitation get the default IPv6 route
 +
    iaid 1
 +
    ia_pd 1/::/56 eth0.2/2/64
 +
    timeout 30
  
# Accept incoming tracked PPP0 connection
+
interface eth0.2
-A IN_PPP0 -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT
+
    ipv6only</pre>
COMMIT
 
  
 +
== Basic IPtables firewall with routing ==
 +
This demonstrates how to set up basic routing with a permissive outgoing firewall. Incoming packets are blocked. The rest is commented in the rule set.
 +
 +
First install iptables:
 +
 +
{{cmd|apk add iptables ip6tables}}
 +
 +
<pre>#########################################################################
 +
# Basic iptables IPv4 routing rule set
 +
#
 +
# 192.168.1.0/24 routed directly to PPP0 via NAT
 +
#
 +
#########################################################################
 +
 +
#
 +
# Mangle Table
 +
# We leave this empty for the moment.
 
#
 
#
# NAT Table
+
*mangle
# This is where translation of packets happens and "forwarding" of ports
 
# to specific hosts.
 
#
 
*nat
 
 
:PREROUTING ACCEPT [0:0]
 
:PREROUTING ACCEPT [0:0]
 
:INPUT ACCEPT [0:0]
 
:INPUT ACCEPT [0:0]
 +
:FORWARD ACCEPT [0:0]
 
:OUTPUT ACCEPT [0:0]
 
:OUTPUT ACCEPT [0:0]
 
:POSTROUTING ACCEPT [0:0]
 
:POSTROUTING ACCEPT [0:0]
 +
COMMIT
  
# Port forwarding for Bittorrent
+
#
-A PREROUTING -i ppp0 -p tcp -m tcp --dport 6881:6889 -j DNAT --to-destination 192.168.1.20
+
# Filter Table
-A PREROUTING -i ppp0 -p udp -m udp --dport 6881:6889 -j DNAT --to-destination 192.168.1.20
+
# This is where we decide to ACCEPT, DROP or REJECT things
 
+
#
# Allows routing to our modem subnet so we can access the web interface or SSH
+
*filter
-A POSTROUTING -s 192.168.1.0/24 -d 192.168.0.1/32 -o eth1 -p tcp -m tcp --dport 22 -j MASQUERADE
+
:INPUT DROP [0:0]
-A POSTROUTING -s 192.168.1.0/24 -d 192.168.0.1/32 -o eth1 -p tcp -m tcp --dport 80 -j MASQUERADE
+
:FORWARD DROP [0:0]
 +
:OUTPUT ACCEPT [0:0]
 +
*filter
  
# Allows hosts of the network to use the PPP tunnel
+
# Create rule chain per input interface for forwarding packets
-A POSTROUTING -s 192.168.1.0/24 -o ppp0 -j MASQUERADE
+
:FWD_ETH0 - [0:0]
COMMIT</pre>
+
:FWD_ETH1 - [0:0]
 +
:FWD_PPP0 - [0:0]
  
I'd also highly suggest reading these resources if you are new to iptables:  
+
# Create rule chain per input interface for input packets (for host itself)
 +
:IN_ETH0 - [0:0]
 +
:IN_ETH1 - [0:0]
 +
:IN_PPP0 - [0:0]
  
* [https://www.frozentux.net/category/linux/iptables Frozen Tux Iptables-tutorial]
+
# Create a log drop chain
* [http://inai.de/links/iptables/ Words of wisdom for #netfilter]
+
:LOG_DROP - [0:0]
* [http://sfvlug.editthis.info/wiki/Things_You_Should_Know_About_Netfilter Things You Should Know About Netfilter]
 
* [http://inai.de/documents/Perfect_Ruleset.pdf Towards the perfect ruleset]
 
  
== /etc/sysctl.d/local.conf ==
+
# Pass input packet to corresponding rule chain
<pre># Controls IP packet forwarding
+
-A INPUT -i lo -j ACCEPT
net.ipv4.ip_forward = 1
+
-A INPUT -i eth0 -j IN_ETH0
 +
-A INPUT -i eth1 -j IN_ETH1
 +
-A INPUT -i ppp0 -j IN_PPP0
  
# Disable IPv6
+
# Pass forwarded packet to corresponding rule chain
net.ipv6.conf.all.disable_ipv6 = 1
+
-A FORWARD -i eth0 -j FWD_ETH0
net.ipv6.conf.lo.disable_ipv6 = 1
+
-A FORWARD -i eth1 -j FWD_ETH1
net.ipv6.conf.default.disable_ipv6 = 1</pre>
+
-A FORWARD -i ppp0 -j FWD_PPP0
  
Note IPv6 is disabled here if you want that see the other tutorial [[Linux Router with VPN on a Raspberry Pi (IPv6)]]. You may also wish to look at [https://www.kernel.org/doc/Documentation/networking/ip-sysctl.txt ip-sysctl.txt] to read about the other keys.
+
# Forward LAN traffic out
 +
-A FWD_ETH0 -s 192.168.1.0/24 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
  
= DHCP =
+
# Forward SSH packets from network to modem
{{cmd|apk add dhcp}}
+
-A FWD_ETH1 -s 192.168.0.0/30 -d 192.168.1.0/24 -p tcp -m tcp --sport 22 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
  
== /etc/conf.d/dhcpd ==
+
# Forward HTTP to modem's webserver
Specify the configuration file location, interface to run on and that you want DHCPD to run in IPv4 mode.
+
-A FWD_ETH1 -s 192.168.0.0/30 -d 192.168.1.0/24 -p tcp -m tcp --sport 80 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
  
<pre># /etc/conf.d/dhcpd: config file for /etc/init.d/dhcpd
+
# Forward traffic to ISP
 +
-A FWD_PPP0 -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT
  
# If you require more than one instance of dhcpd you can create symbolic
+
# SSH to Router
# links to dhcpd service like so
+
-A IN_ETH0 -s 192.168.1.0/24 -p tcp -m tcp --dport 22 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
#  cd /etc/init.d
 
#  ln -s dhcpd dhcpd.foo
 
#  cd ../conf.d
 
#  cp dhcpd dhcpd.foo
 
# Now you can edit dhcpd.foo and specify a different configuration file.
 
# You'll also need to specify a pidfile in that dhcpd.conf file.
 
# See the pid-file-name option in the dhcpd.conf man page for details.
 
  
# If you wish to run dhcpd in a chroot, uncomment the following line
+
# DNS to Router
# DHCPD_CHROOT="/var/lib/dhcp/chroot"
+
-A IN_ETH0 -s 192.168.1.0/24 -p tcp -m tcp --dport 1812 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
  
# All file paths below are relative to the chroot.
+
# FreeRadius Client (eg a UniFi AP)
# You can specify a different chroot directory but MAKE SURE it's empty.
+
-A IN_ETH0 -s 192.168.1.0/24 -p udp -m udp --dport 1812 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
  
# Specify a configuration file - the default is /etc/dhcp/dhcpd.conf
+
# NTP to Router
DHCPD_CONF="/etc/dhcp/dhcpd.conf"
+
-A IN_ETH0 -s 192.168.1.0/24 -p udp -m udp --dport 123 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
  
# Configure which interface or interfaces to for dhcpd to listen on.
+
# Accept traffic
# List all interfaces space separated. If this is not specified then
+
-A IN_ETH0 -s 192.168.1.0/24 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
# we listen on all interfaces.
 
DHCPD_IFACE="eth0"
 
  
# Insert any other dhcpd options - see the man page for a full list.
+
# SSH To Modem from Router
DHCPD_OPTS="-4"</pre>
+
-A IN_ETH1 -s 192.168.0.1/32 -d 192.168.0.0/30 -p tcp -m tcp --sport 22 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
  
== /etc/dhcp/dhcpd.conf ==
+
# HTTP to modem
Configure your DHCP configuration server. For my DHCP server I'm going to have three subnets. Each has a specific purpose. You may choose to have any number of subnets like below. The broadcast-address would be different if you used VLANs. However in this case we are not.
+
-A IN_ETH1 -s 192.168.0.1/32 -d 192.168.0.0/30 -p tcp -m tcp --sport 80 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
  
<pre>authoritative;
+
# Accept incoming tracked PPP0 connection
ddns-update-style interim;
+
-A IN_PPP0 -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT
 +
COMMIT
  
shared-network home {
+
#
  subnet 192.168.1.0 netmask 255.255.255.0 {
+
# NAT Table
    range 192.168.1.10 192.168.1.240;
+
# This is where translation of packets happens and "forwarding" of ports
    option subnet-mask 255.255.255.0;
+
# to specific hosts.
    option broadcast-address 192.168.1.255;
+
#
    option routers 192.168.1.1;
+
*nat
    option ntp-servers 192.168.1.1;
+
:PREROUTING ACCEPT [0:0]
    option domain-name-servers 192.168.1.1;
+
:INPUT ACCEPT [0:0]
    allow unknown-clients;
+
:OUTPUT ACCEPT [0:0]
  }
+
:POSTROUTING ACCEPT [0:0]
  
  subnet 192.168.2.0 netmask 255.255.255.0 {
+
# Port forwarding for Bittorrent
    range 192.168.2.10 192.168.2.240;
+
-A PREROUTING -i ppp0 -p tcp -m tcp --dport 6881:6889 -j DNAT --to-destination 192.168.1.20
    option subnet-mask 255.255.255.0;
+
-A PREROUTING -i ppp0 -p udp -m udp --dport 6881:6889 -j DNAT --to-destination 192.168.1.20
    option broadcast-address 192.168.2.255;
 
    option routers 192.168.2.1;
 
    option ntp-servers 192.168.2.1;
 
    option domain-name-servers 192.168.1.1;
 
    ignore unknown-clients;
 
  }
 
  
  subnet 192.168.3.0 netmask 255.255.255.0 {
+
# Allows routing to our modem subnet so we can access the web interface or SSH
    range 192.168.3.10 192.168.3.240;
+
-A POSTROUTING -s 192.168.1.0/24 -d 192.168.0.1/32 -o eth1 -p tcp -m tcp --dport 22 -j MASQUERADE
    option subnet-mask 255.255.255.0;
+
-A POSTROUTING -s 192.168.1.0/24 -d 192.168.0.1/32 -o eth1 -p tcp -m tcp --dport 80 -j MASQUERADE
    option broadcast-address 192.168.3.255;
 
    option routers 192.168.3.1;
 
    option ntp-servers 192.168.3.1;
 
    option domain-name-servers 192.168.1.1;
 
    ignore unknown-clients;
 
  }
 
}
 
  
host Gaming_Computer {
+
# Allows hosts of the network to use the PPP tunnel
  hardware ethernet 00:53:00:FF:FF:11;
+
-A POSTROUTING -s 192.168.1.0/24 -o ppp0 -j MASQUERADE
  fixed-address 192.168.1.20;
+
COMMIT</pre>
  option subnet-mask 255.255.255.0;
 
  option broadcast-address 192.168.1.255;
 
  option routers 192.168.1.1;
 
  option host-name "gaming_computer";
 
}
 
  
host Linux_Workstation {
+
I'd also highly suggest reading these resources if you are new to iptables:  
  hardware ethernet 00:53:00:FF:FF:22;
 
  fixed-address 192.168.2.21;
 
  option subnet-mask 255.255.255.0;
 
  option broadcast-address 192.168.2.255;
 
  option routers 192.168.2.1;
 
  option host-name "linux_workstation";
 
}
 
  
host printer {
+
* [https://www.frozentux.net/category/linux/iptables Frozen Tux Iptables-tutorial]
  hardware ethernet 00:53:00:FF:FF:33;
+
* [http://inai.de/links/iptables/ Words of wisdom for #netfilter]
  fixed-address 192.168.3.9;
+
* [http://sfvlug.editthis.info/wiki/Things_You_Should_Know_About_Netfilter Things You Should Know About Netfilter]
  option subnet-mask 255.255.255.0;
+
* [http://inai.de/documents/Perfect_Ruleset.pdf Towards the perfect ruleset]
  option broadcast-address 192.168.3.255;
 
  option routers 192.168.3.1;
 
}</pre>
 
  
Make sure to add this to the default run level once configured:
+
== /etc/sysctl.d/local.conf ==
{{cmd|rc-update add dhcpd default}}
+
<pre># Controls IP packet forwarding
 +
net.ipv4.ip_forward = 1
  
= Synchronizing the clock =
+
# Needed to use fwmark, only required if you want to set up the VPN subnet later in this article
 +
net.ipv4.conf.all.rp_filter = 2
  
You can choose to use BusyBox's ntpd or you can choose a more fully fledged option like [http://www.openntpd.org OpenNTPD]
+
# Disable IPv6
 +
net.ipv6.conf.all.disable_ipv6 = 1
 +
net.ipv6.conf.lo.disable_ipv6 = 1
 +
net.ipv6.conf.default.disable_ipv6 = 1</pre>
  
== Busybox /etc/conf.d/ntpd ==
+
Note IPv6 is disabled here if you want that see the other tutorial [[Linux Router with VPN on a Raspberry Pi (IPv6)]]. You may also wish to look at [https://www.kernel.org/doc/Documentation/networking/ip-sysctl.txt ip-sysctl.txt] to read about the other keys.
Allow clients to synchronize their clocks with the router.
 
  
<pre># By default ntpd runs as a client. Add -l to run as a server on port 123.
+
= DHCP =
NTPD_OPTS="-l -N -p <REMOTE TIME SERVER>"</pre>
+
{{cmd|apk add dhcp}}
  
Make sure to add this to the default run level once configured:
+
== /etc/conf.d/dhcpd ==
{{cmd|rc-update add ntpd default}}
+
Specify the configuration file location, interface to run on and that you want DHCPD to run in IPv4 mode.
  
Or if you prefer to synchronize with multiple servers...
+
<pre># /etc/conf.d/dhcpd: config file for /etc/init.d/dhcpd
  
== OpenNTPD /etc/ntpd.conf ==
+
# If you require more than one instance of dhcpd you can create symbolic
 
+
# links to dhcpd service like so
Install OpenNTPD
+
#  cd /etc/init.d
{{cmd|apk add openntpd}}
+
#  ln -s dhcpd dhcpd.foo
 +
#  cd ../conf.d
 +
#  cp dhcpd dhcpd.foo
 +
# Now you can edit dhcpd.foo and specify a different configuration file.
 +
# You'll also need to specify a pidfile in that dhcpd.conf file.
 +
# See the pid-file-name option in the dhcpd.conf man page for details.
  
Add to default run level.
+
# If you wish to run dhcpd in a chroot, uncomment the following line
{{cmd|rc-update add openntpd default}}
+
# DHCPD_CHROOT="/var/lib/dhcp/chroot"
  
=== /etc/ntpd.conf ===
+
# All file paths below are relative to the chroot.
<pre># sample ntpd configuration file, see ntpd.conf(5)
+
# You can specify a different chroot directory but MAKE SURE it's empty.
  
# Addresses to listen on (ntpd does not listen by default)
+
# Specify a configuration file - the default is /etc/dhcp/dhcpd.conf
listen on 192.168.1.1
+
DHCPD_CONF="/etc/dhcp/dhcpd.conf"
listen on 192.168.2.1
 
  
# sync to a single server
+
# Configure which interface or interfaces to for dhcpd to listen on.
#server ntp.example.org
+
# List all interfaces space separated. If this is not specified then
 +
# we listen on all interfaces.
 +
DHCPD_IFACE="eth0"
  
# use a random selection of NTP Pool Time Servers
+
# Insert any other dhcpd options - see the man page for a full list.
# see http://support.ntp.org/bin/view/Servers/NTPPoolServers
+
DHCPD_OPTS="-4"</pre>
server 0.pool.ntp.org
 
server 1.pool.ntp.org
 
server 2.pool.ntp.org
 
server 3.pool.ntp.org</pre>
 
  
== tlsdate ==
+
== /etc/dhcp/dhcpd.conf ==
The time can also be extracted from a https handshake. If the certificate is self-signed you will need to use skip-verification:
+
Configure your DHCP configuration server. For my DHCP server I'm going to have three subnets. Each has a specific purpose. You may choose to have any number of subnets like below. The broadcast-address would be different if you used VLANs. However in this case we are not.
  
{{cmd|apk add tlsdate}}
+
<pre>authoritative;
{{cmd|tlsdate -V --skip-verification -p 80 -H example.com}}
+
ddns-update-style interim;
  
== timezone ==
+
shared-network home {
You might also want to set a timezone, see [[Setting the timezone]].
+
  subnet 192.168.1.0 netmask 255.255.255.0 {
 +
    range 192.168.1.10 192.168.1.240;
 +
    option subnet-mask 255.255.255.0;
 +
    option broadcast-address 192.168.1.255;
 +
    option routers 192.168.1.1;
 +
    option ntp-servers 192.168.1.1;
 +
    option domain-name-servers 192.168.1.1;
 +
    allow unknown-clients;
 +
  }
  
= Saving Time =
+
  subnet 192.168.2.0 netmask 255.255.255.0 {
There are two ways to do this. If you didn't buy an RTC clock see [[Saving time with Software Clock]]. If you did like the PiFace Real Time Clock see [[Saving time with Hardware Clock]]
+
    range 192.168.2.10 192.168.2.240;
 +
    option subnet-mask 255.255.255.0;
 +
    option broadcast-address 192.168.2.255;
 +
    option routers 192.168.2.1;
 +
    option ntp-servers 192.168.2.1;
 +
    option domain-name-servers 192.168.1.1;
 +
    ignore unknown-clients;
 +
  }
  
= Unbound DNS forwarder with dnscrypt =
+
  subnet 192.168.3.0 netmask 255.255.255.0 {
We want to be able to do our lookups using [http://dnscrypt.org dnscrypt] without installing dnscrypt on every client on the network. Therefore the router will also run a DNS forwarder and request unknown domains over dnscrypt for our clients.
+
    range 192.168.3.10 192.168.3.240;
 +
    option subnet-mask 255.255.255.0;
 +
    option broadcast-address 192.168.3.255;
 +
    option routers 192.168.3.1;
 +
    option ntp-servers 192.168.3.1;
 +
    option domain-name-servers 192.168.1.1;
 +
    ignore unknown-clients;
 +
  }
 +
}
  
== Unbound ==
+
host Gaming_Computer {
First install {{cmd|apk add unbound}}
+
  hardware ethernet 00:53:00:FF:FF:11;
 +
  fixed-address 192.168.1.20;
 +
  option subnet-mask 255.255.255.0;
 +
  option broadcast-address 192.168.1.255;
 +
  option routers 192.168.1.1;
 +
  option host-name "gaming_computer";
 +
}
  
=== /etc/unbound/unbound.conf ===
+
host Linux_Workstation {
<pre># unbound.conf(5) man page.
+
  hardware ethernet 00:53:00:FF:FF:22;
#
+
  fixed-address 192.168.2.21;
# See /usr/share/doc/unbound/examples/unbound.conf for a commented
+
  option subnet-mask 255.255.255.0;
# reference config file.
+
  option broadcast-address 192.168.2.255;
 +
  option routers 192.168.2.1;
 +
  option host-name "linux_workstation";
 +
}
  
server:
+
host printer {
    # The following line will configure unbound to perform cryptographic
+
  hardware ethernet 00:53:00:FF:FF:33;
    # DNSSEC validation using the root trust anchor.
+
  fixed-address 192.168.3.9;
    # auto-trust-anchor-file: "/var/lib/unbound/root.key"
+
  option subnet-mask 255.255.255.0;
server:
+
  option broadcast-address 192.168.3.255;
verbosity: 1
+
  option routers 192.168.3.1;
num-threads: 4                                                       
+
}</pre>
interface: 192.168.1.1
 
do-ip4: yes
 
do-udp: yes
 
do-tcp: yes
 
access-control: 192.168.1.0/24 allow  # Specify the subnets you want to listen on
 
access-control: 192.168.2.0/24 allow
 
do-not-query-localhost: no
 
chroot: ""     
 
logfile: "/var/log/unbound.log"           
 
use-syslog: no
 
hide-identity: yes
 
hide-version: yes
 
harden-glue: yes
 
harden-dnssec-stripped: yes
 
use-caps-for-id: yes     
 
private-domain: "<HOSTNAME>"     
 
#local-zone: "localhost." static
 
#local-data: "freebox.localhost. IN A 192.168.0.254"                                             
 
#local-data-ptr: "192.168.0.254 freebox.localhost"
 
python:
 
remote-control:
 
forward-zone:
 
  name: "."
 
  forward-addr: 127.0.0.2@53</pre>
 
  
=== /etc/network/interfaces ===
+
Make sure to add this to the default run level once configured:
You'll need a second loopback device, put it under the already existing one.
+
{{cmd|rc-update add dhcpd default}}
  
<pre># Loopback interfaces
+
= Synchronizing the clock =
auto lo
 
iface lo inet loopback
 
  address 127.0.0.1
 
  netmask 255.0.0.0
 
  
auto lo:1
+
You can choose to use BusyBox's ntpd or you can choose a more fully fledged option like [http://www.openntpd.org OpenNTPD] or [https://chrony.tuxfamily.org Chrony]
iface lo:1 inet static
 
  address 127.0.0.2
 
  netmask 255.0.0.0</pre>
 
  
== Blocking nasties on the network by domain ==
+
== Busybox /etc/conf.d/ntpd ==
It seems Microsoft has added a whole bunch of telemetry (spyware) analytics to Windows itself, whereby the OS now calls home with various information regarding it's usage. Back porting to previous versions of Windows is not an option, because the telemetry patches have also been back ported to 7/8.1.
+
Allow clients to synchronize their clocks with the router.
  
Changing the knobs in Windows to stop this activity doesn't silence it completely, and they can always be reset with another update from Microsoft. It is however unlikely they will change the domains that are looked up. More information about that can be found [https://www.privacytools.io/#win10 here]. You should also consider ditching Windows entirely and using a proper operating system that does not contain intrusive malware [https://www.privacytools.io/#os here are a few choices to consider].
+
<pre># By default ntpd runs as a client. Add -l to run as a server on port 123.
 +
NTPD_OPTS="-l -N -p <REMOTE TIME SERVER>"</pre>
  
As this is a network router, it might be prudent to block those domains.
+
Make sure to add this to the default run level once configured:
 +
{{cmd|rc-update add ntpd default}}
  
This script takes in a list of domains and produces a filter file. We are directing all lookups to "0.0.0.1" which is an invalid IP and should fail immediately, unlike localhost. There are lists of the addresses in various places such as [https://www.reddit.com/r/privacy/comments/3htei2/stop_windows_10_from_phoning_home_by_blocking/cuafuvg here] and in this [https://github.com/10se1ucgo/DisableWinTracking/blob/master/run.py#L188 script].
+
Or if you prefer to synchronize with multiple servers...
  
You could also use this to block advertising, but that's probably easier to do in a web browser with something like [https://en.wikipedia.org/wiki/UBlock UBlock/UBlock Origin].
+
== Chrony /etc/chrony.conf ==
 +
{{cmd|apk add chrony}}
  
=== /etc/unbound/unbound.conf ===
+
<pre>logdir /var/log/chrony
In your main unbound configuration add
+
log measurements statistics tracking
<pre>include: /etc/unbound/filter.conf</pre>
 
  
=== Script to prepare/sort domains for Unbound  ===
+
allow 192.168.0.0/30
<pre>#!/bin/sh
+
allow 192.168.1.0/24
 +
allow 192.168.2.0/24
 +
allow 192.168.3.0/24
 +
allow 192.168.4.0/24
 +
broadcast 30 192.168.0.3
 +
broadcast 30 192.168.1.255
 +
broadcast 30 192.168.2.255
 +
broadcast 30 192.168.3.255
 +
broadcast 30 192.168.4.255
  
##################################################
+
server 0.pool.ntp.org iburst
# Script taken from http://npr.me.uk/unbound.html
+
server 1.pool.ntp.org iburst
# Note you need GNU sed
+
server 2.pool.ntp.org iburst
##################################################
+
server 3.pool.ntp.org iburst
  
# Remove "#" comments
+
initstepslew 10 pool.ntp.org
# Remove space and tab
+
driftfile /var/lib/chrony/chrony.drift
# Remove blank lines
+
hwclockfile /etc/adjtime
# Remove localhost and broadcasthost lines
+
rtcdevice /dev/rtc0
# Keep just the hosts
+
rtcsync</pre>
# Remove leading and trailing space and tab (again)
 
# Make everything lower case
 
  
sed -e "s/#.*//" \
+
== OpenNTPD /etc/ntpd.conf ==
    -e "s/[ \x09]*$//"\
 
    -e "/^$/ d" \
 
    -e "/^.*local.*/ d" \
 
    -e "/^.*broadcasthost.*/ d" \
 
    -e "s/\(^.*\) \([a-zA-Z0-9\.\-]*\)/\2/" \
 
    -e "s/^[ \x09]*//;s/[ \x09]*$//" $1 \
 
    -e "s/\(.*\)/\L\1/" hosts.txt > temp1.txt
 
  
# Remove any duplicate hosts
+
Install OpenNTPD
 +
{{cmd|apk add openntpd}}
  
sort temp1.txt | uniq >temp2.txt
+
Add to default run level.
 +
{{cmd|rc-update add openntpd default}}
  
# Remove any hosts starting with "."
+
=== /etc/ntpd.conf ===
# Create the two required lines for each host.
+
<pre># sample ntpd configuration file, see ntpd.conf(5)
  
sed -e "/^\..*/ d" \
+
# Addresses to listen on (ntpd does not listen by default)
    -e "s/\(^.*\)/local-zone: \x22\1\x22 redirect\nlocal-data: \x22\1 A 0.0.0.1\x22/" \
+
listen on 192.168.1.1
      temp2.txt > filter.conf
+
listen on 192.168.2.1
  
# Clean up
+
# sync to a single server
rm temp1.txt
+
#server ntp.example.org
rm temp2.txt</pre>
 
  
== /etc/unbound/filter.conf ==
+
# use a random selection of NTP Pool Time Servers
<pre>local-zone: "a-0001.a-msedge.net" redirect
+
# see http://support.ntp.org/bin/view/Servers/NTPPoolServers
local-data: "a-0001.a-msedge.net A 0.0.0.1"
+
server 0.pool.ntp.org
local-zone: "a-0002.a-msedge.net" redirect
+
server 1.pool.ntp.org
local-data: "a-0002.a-msedge.net A 0.0.0.1"
+
server 2.pool.ntp.org
local-zone: "a-0003.a-msedge.net" redirect
+
server 3.pool.ntp.org</pre>
local-data: "a-0003.a-msedge.net A 0.0.0.1"
+
 
local-zone: "a-0004.a-msedge.net" redirect
+
== tlsdate ==
local-data: "a-0004.a-msedge.net A 0.0.0.1"
+
The time can also be extracted from a https handshake. If the certificate is self-signed you will need to use skip-verification:
local-zone: "a-0005.a-msedge.net" redirect
+
 
local-data: "a-0005.a-msedge.net A 0.0.0.1"
+
{{cmd|apk add tlsdate}}
local-zone: "a-0006.a-msedge.net" redirect
+
{{cmd|tlsdate -V --skip-verification -p 80 -H example.com}}
local-data: "a-0006.a-msedge.net A 0.0.0.1"
+
 
local-zone: "a-0007.a-msedge.net" redirect
+
== timezone ==
local-data: "a-0007.a-msedge.net A 0.0.0.1"
+
You might also want to set a timezone, see [[Setting the timezone]].
 
+
 
 +
= Saving Time =
 +
There are two ways to do this. If you didn't buy an RTC clock see [[Saving time with Software Clock]]. If you did like the PiFace Real Time Clock see [[Saving time with Hardware Clock]]
 +
 
 +
= Unbound DNS forwarder with dnscrypt =
 +
We want to be able to do our lookups using [https://dnscrypt.info/ dnscrypt] without installing DNSCrypt on every client on the network. DNSCrypt can use it's [https://dnscrypt.info/protocol own protocol] or [https://en.wikipedia.org/wiki/DNS_over_HTTPS DNS over HTTPS].
 +
 
 +
The router will also run a DNS forwarder and request unknown domains over DNSCrypt for our clients. Borrowed from the ArchLinux wiki article on [https://wiki.archlinux.org/index.php/dnscrypt-proxy dnscrypt-proxy].
 +
 
 +
== Unbound ==
 +
First install {{cmd|apk add unbound}}
 +
 
 +
=== /etc/unbound/unbound.conf ===
 +
<pre>server:
 +
    # Use this to include other text into the file.
 +
    include: "/etc/unbound/filter.conf"
 +
 
 +
    # verbosity number, 0 is least verbose. 1 is default.
 +
    verbosity: 1
 +
 
 +
    # specify the interfaces to answer queries from by ip-address.
 +
    # The default is to listen to localhost (127.0.0.1 and ::1).
 +
    # specify 0.0.0.0 and ::0 to bind to all available interfaces.
 +
    # specify every interface[@port] on a new 'interface:' labelled line.
 +
    # The listen interfaces are not changed on reload, only on restart.
 +
    interface: 192.168.2.1
 +
    interface: 192.168.3.1
 +
 
 +
    # Enable IPv4, "yes" or "no".
 +
    do-ip4: yes
 +
 
 +
    # Enable IPv6, "yes" or "no".
 +
    do-ip6: yes
 +
 
 +
    # Enable UDP, "yes" or "no".
 +
    do-udp: yes
 +
 
 +
    # Enable TCP, "yes" or "no".
 +
    do-tcp: yes
 +
 
 +
    # control which clients are allowed to make (recursive) queries
 +
    # to this server. Specify classless netblocks with /size and action.
 +
    # By default everything is refused, except for localhost.
 +
    # Choose deny (drop message), refuse (polite error reply),
 +
    # allow (recursive ok), allow_setrd (recursive ok, rd bit is forced on),
 +
    # allow_snoop (recursive and nonrecursive ok)
 +
    # deny_non_local (drop queries unless can be answered from local-data)
 +
    # refuse_non_local (like deny_non_local but polite error reply).
 +
    # access-control: 0.0.0.0/0 refuse
 +
    # access-control: 127.0.0.0/8 allow
 +
    # access-control: ::0/0 refuse
 +
    # access-control: ::1 allow
 +
    # access-control: ::ffff:127.0.0.1 allow
 +
    access-control: 192.168.1.0/24 allow
 +
    access-control: 192.168.2.0/24 allow
 +
    access-control: 192.168.3.0/24 allow
 +
 
 +
    # the log file, "" means log to stderr.
 +
    # Use of this option sets use-syslog to "no".
 +
    logfile: "/var/log/unbound/unbound.log"
 +
 
 +
    # Log to syslog(3) if yes. The log facility LOG_DAEMON is used to
 +
    # log to. If yes, it overrides the logfile.
 +
    use-syslog: no
 +
 
 +
    # print one line with time, IP, name, type, class for every query.
 +
    # log-queries: no
 +
 
 +
    # print one line per reply, with time, IP, name, type, class, rcode,
 +
    # timetoresolve, fromcache and responsesize.
 +
    # log-replies: no
 +
 
 +
    # enable to not answer id.server and hostname.bind queries.
 +
    hide-identity: yes
 +
 
 +
    # enable to not answer version.server and version.bind queries.
 +
    # hide-version: yes
 +
 
 +
    # enable to not answer trustanchor.unbound queries.
 +
    hide-trustanchor: yes
 +
 
 +
 
 +
    # Harden against very small EDNS buffer sizes.
 +
    harden-short-bufsize: yes
 +
 
 +
    # Harden against unseemly large queries.
 +
    harden-large-queries: yes
 +
 
 +
    # Harden against out of zone rrsets, to avoid spoofing attempts.
 +
    harden-glue: yes
 +
 
 +
    # Harden against receiving dnssec-stripped data. If you turn it
 +
    # off, failing to validate dnskey data for a trustanchor will
 +
    # trigger insecure mode for that zone (
  
rngtest: starting FIPS tests...
+
=== /etc/dnscrypt-proxy/dnscrypt-proxy.toml ===
rngtest: bits received from input: 20000032
+
Using the sample dnscrypt config is fine, you will need to make these changes:
rngtest: FIPS 140-2 successes: 1000
+
 
rngtest: FIPS 140-2 failures: 0
+
<pre>listen_addresses = ['127.0.0.1:53000', '[::1]:53000']
rngtest: FIPS 140-2(2001-10-10) Monobit: 0
+
proxy = "socks5://127.0.0.1:1080"</pre>
rngtest: FIPS 140-2(2001-10-10) Poker: 0
 
rngtest: FIPS 140-2(2001-10-10) Runs: 0
 
rngtest: FIPS 140-2(2001-10-10) Long run: 0
 
rngtest: FIPS 140-2(2001-10-10) Continuous run: 0
 
rngtest: input channel speed: (min=117.709; avg=808.831; max=3255208.333)Kibits/s
 
rngtest: FIPS tests speed: (min=17.199; avg=22.207; max=22.653)Mibits/s
 
rngtest: Program run time: 25178079 microseconds</pre>
 
  
It's possible you might have a some failures. That's okay, two runs I did previously had a failure each.
+
== Dante ==
 +
First install dante, you'll need to pin the testing repository. See: [[Alpine Linux package management#Repository pinning]].
  
= WiFi 802.1x EAP and FreeRadius =
+
{{cmd|apk add dante-server@testing}}
A more secure way than using pre-shared keys (WPA2) is to use [https://en.wikipedia.org/wiki/Extensible_Authentication_Protocol#EAP-TLS EAP-TLS] and use separate certificates for each device. See [[FreeRadius EAP-TLS configuration]]
 
  
= VPN Tunnel on specific subnet =
+
Configure it like so:
As mentioned earlier in this article it might be useful to have a VPN subnet and a non-VPN subnet. Typically gaming consoles or computers might want low-latency connections. For this exercise we use fwmark.
 
  
We expand the network to look like this:
+
=== /etc/sockd.conf ===
 +
<pre>logoutput: stderr
 +
internal: 127.0.0.1 port = 1080
 +
external: tun0
 +
clientmethod: none
 +
socksmethod: none
 +
user.unprivileged: sockd
  
[[File:Network diagram ipv4 tunnel.svg|900px|center|Network Diagram with IPv4 tunnel]]
+
# Allow connections from localhost to any host
 +
client pass {
 +
        from: 127.0.0.1/8 to: 0.0.0.0/0
 +
log: error # connect/disconnect
 +
}
  
Install the necessary packages:
+
# Generic pass statement - bind/outgoing traffic
{{cmd|apk add openvpn iproute2 iputils}}
+
socks pass {
 +
        from: 0.0.0.0/0 to: 0.0.0.0/0
 +
        command: bind connect udpassociate
 +
        log: error # connect disconnect iooperation
 +
}
  
== /etc/modules ==
+
# Generic pass statement for incoming connections/packets
You'll want to add the tun module
+
socks pass {
<pre>tun</pre>
+
        from: 0.0.0.0/0 to: 0.0.0.0/0
 +
        command: bindreply udpreply
 +
        log: error # connect disconnect iooperation
 +
}</pre>
  
== /etc/iproute2/rt_tables ==
+
Finally the services to the the default run level:
Add the two routing tables to the bottom of rt_tables. It should look something like this:
+
{{cmd|rc-update add sockd default}}
<pre>#
+
{{cmd|rc-update add unbound default}}
# reserved values
+
{{cmd|rc-update add dnscrypt-proxy default}}
#
 
255 local
 
254 main
 
253 default
 
0 unspec
 
#
 
# local
 
#
 
#1 inr.ruhep
 
1 ISP
 
2 VPN</pre>
 
  
== /etc/network/interfaces ==
+
= Random number generation =
Next up add the virtual interface (really just a IP address to eth0) eth0:2, just under eth0 will do.
+
There are two ways to assist with random number generation [[Entropy and randomness]]. This can be particularly useful if you're generating your own Diffie-Hellman nonce file, used in the [[FreeRadius EAP-TLS configuration]] section. Or for that matter any process which requires lots of random number generation such as generating certificates or public private keys.
  
<pre># Route to VPN subnet
+
== Haveged ==
auto eth0:2
+
[http://www.issihosts.com/haveged Haveged] is a great way to improve random number generation speed. It uses the unpredictable random number generator based upon an adaptation of the [http://www.irisa.fr/caps/projects/hipsor/ HAVEGE] algorithm.
iface eth0:2 inet static
 
  address 192.168.2.1
 
  netmask 255.255.255.0
 
  broadcast 192.168.2.255
 
  post-up /etc/network/fwmark_rules</pre>
 
  
== /etc/sysctl.conf ==
+
Install haveged:
If you want to use fwmark rules you need to change this setting. It causes the router to still do source validation.
+
{{cmd|apk add haveged}}
  
<pre>net.ipv4.conf.all.rp_filter = 2</pre>
+
Start haveged service:
 +
{{cmd|service haveged start}}
  
fwmark won't work if you have this set to 1.
+
Add service to boot
 +
{{cmd|rc-update add haveged default}}
  
== /etc/network/fwmark_rules ==
+
Start rngd service:
In this file we want to put the fwmark rules and set the correct priorities.
+
{{cmd|service haveged start}}
  
<pre>#!/bin/sh
+
Add service to boot:
 +
{{cmd|rc-update add haveged default}}
  
# Normal packets to go direct out WAN
+
== rng-tools with bcm2708-rng ==
/sbin/ip rule add fwmark 1 table ISP prio 100
 
  
# Put packets destined into VPN when VPN is up
+
=== Pre Alpine Linux 3.8 (which includes rngd 5) ===
/sbin/ip rule add fwmark 2 table VPN prio 200
+
All Raspberry Pis come with the bcm2708-rng random number generator on board. If you are doing this project on a Raspberry Pi then you may choose to use this also.
  
# Prevent packets from being routed out when VPN is down.
+
Add the kernel module to /etc/modules:
# This prevents packets from falling back to the main table
+
{{cmd|echo "bcm2708-rng" > /etc/modules}}
# that has a priority of 32766
 
/sbin/ip rule add prohibit fwmark 2 prio 300</pre>
 
  
== /etc/ppp/ip-up ==
+
Insert module:
Next up we want to create the routes that should be run when PPP comes online. There are special hooks we can use in ip-up and ip-down to refer to the IP address, [https://ppp.samba.org/pppd.html#sect13 ppp man file - Scripts ] You can also read about them in your man file if you have ppp-doc installed.
+
{{cmd|modprobe bcm2708-rng}}
  
<pre>#!/bin/sh
+
Install rng-tools:
#
+
{{cmd|apk add rng-tools}}
# This script is run by pppd when there's a successful ppp connection.
 
#
 
  
# Flush out any old rules that might be there
+
Set the random device (/dev/random) and rng device (/dev/hwrng) in /etc/conf.d/rngd
/sbin/ip route flush table ISP
+
{{cmd|<nowiki>RNGD_OPTS="--no-drng=1 --no-tpm=1 -o /dev/random -r /dev/hwrng"</nowiki>}}
  
# Add route to table from subnets on LAN
+
=== Post Alpine Linux 3.8 (which includes rngd 6) ===
/sbin/ip route add 192.168.1.0/24 dev eth0 table ISP
 
/sbin/ip route add 192.168.2.0/24 dev eth0 table ISP
 
  
# Add route from IP given by ISP to the table
+
With AlpineLinux 3.8 you don't have to insert the module as it is already built in the kernel.
/sbin/ip rule add from ${IPREMOTE} table ISP prio 100
 
  
# Add a default route
+
Additionally the syntax has changed for rngd so for /etc/conf.d/rngd you'll need
/sbin/ip route add table ISP default via ${IPREMOTE} dev ${IFNAME}</pre>
 
  
== /etc/ppp/ip-down ==
+
{{cmd|<nowiki>RNGD_OPTS="-x1 -o /dev/random -r /dev/hwrng"</nowiki>}}
<pre>#!/bin/sh
 
#
 
# This script is run by pppd after the connection has ended.
 
#
 
  
# Delete the rules when we take the interface down
+
Start rngd service:
/sbin/ip rule del from ${IPREMOTE} table ISP prio 100</pre>
+
{{cmd|service rngd start}}
  
== /etc/openvpn/route-up-fwmark.sh ==
+
Add service to boot:
OpenVPN needs similar routing scripts and it also has it's own special hooks that allow you to specify particular values. A full list is here [https://openvpn.net/index.php/open-source/documentation/manuals/65-openvpn-20x-manpage.html#lbAS OpenVPN man file - Environmental Variables]
+
{{cmd|rc-update add rngd default}}
  
<pre>#!/bin/sh
+
You can test it with:
#
+
{{cmd|<nowiki>cat /dev/hwrng | rngtest -c 1000</nowiki>}}
# This script is run by OpenVPN when there's a successful VPN connection.
 
#
 
  
# Flush out any old rules that might be there
+
You should see something like:
/sbin/ip route flush table VPN
 
  
# Add route to table from 192.168.2.0/24 subnet on LAN
+
<pre>rngtest 5
/sbin/ip route add 192.168.2.0/24 dev eth0 table VPN
+
Copyright (c) 2004 by Henrique de Moraes Holschuh
 +
This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  
# Add route from VPN interface IP to the VPN table
+
rngtest: starting FIPS tests...
/sbin/ip rule add from ${ifconfig_local} table VPN prio 200
+
rngtest: bits received from input: 20000032
 
+
rngtest: FIPS 140-2 successes: 1000
# Add a default route
+
rngtest: FIPS 140-2 failures: 0
/sbin/ip route add default via ${ifconfig_local} dev ${dev} table VPN</pre>
+
rngtest: FIPS 140-2(2001-10-10) Monobit: 0
 +
rngtest: FIPS 140-2(2001-10-10) Poker: 0
 +
rngtest: FIPS 140-2(2001-10-10) Runs: 0
 +
rngtest: FIPS 140-2(2001-10-10) Long run: 0
 +
rngtest: FIPS 140-2(2001-10-10) Continuous run: 0
 +
rngtest: input channel speed: (min=117.709; avg=808.831; max=3255208.333)Kibits/s
 +
rngtest: FIPS tests speed: (min=17.199; avg=22.207; max=22.653)Mibits/s
 +
rngtest: Program run time: 25178079 microseconds</pre>
  
== /etc/openvpn/route-pre-down-fwmark.sh ==
+
It's possible you might have a some failures. That's okay, two runs I did previously had a failure each.
  
<pre>#!/bin/sh
+
= WiFi 802.1x EAP and FreeRadius =
#
+
A more secure way than using pre-shared keys (WPA2) is to use [https://en.wikipedia.org/wiki/Extensible_Authentication_Protocol#EAP-TLS EAP-TLS] and use separate certificates for each device. See [[FreeRadius EAP-TLS configuration]]
# This script is run by OpenVPN after the connection has ended
 
#
 
  
# Delete the rules when we take the interface down
+
= VPN Tunnel on specific subnet =
/sbin/ip rule del from ${ifconfig_local} table VPN prio 200</pre>
+
As mentioned earlier in this article it might be useful to have a VPN subnet and a non-VPN subnet. Typically gaming consoles or computers might want low-latency connections. For this exercise we use fwmark.
  
What I did find was when starting and stopping the OpenVPN service if you used:
+
We expand the network to look like this:
  
{{cmd|service openvpn stop}}
+
[[File:Network diagram ipv4 tunnel.svg|900px|center|Network Diagram with IPv4 tunnel]]
  
The rules in route-pre-down-fwmark.sh were not executed.
+
Install the necessary packages:
 +
{{cmd|apk add openvpn iproute2 iputils}}
  
However:
+
== /etc/modules ==
 +
You'll want to add the tun module
 +
<pre>tun</pre>
  
{{cmd|/etc/init.d/openvpn stop}}
+
== /etc/iproute2/rt_tables ==
 +
Add the two routing tables to the bottom of rt_tables. It should look something like this:
 +
<pre>#
 +
# reserved values
 +
#
 +
255 local
 +
254 main
 +
253 default
 +
0 unspec
 +
#
 +
# local
 +
#
 +
#1 inr.ruhep
 +
1 ISP
 +
2 VPN</pre>
  
seemed to work correctly.
+
== /etc/network/interfaces ==
 +
Next up add the virtual interface (really just a IP address to eth0) eth0:2, just under eth0 will do.
  
== Advanced IPtables rules that allow us to route into our two routing tables ==
+
<pre># Route to VPN subnet
This is an expansion of the previous set of rules. It sets up NAT masquerading for the 192.168.2.0 to go through the VPN using marked packets.
+
auto eth0:2
 +
iface eth0:2 inet static
 +
  address 192.168.2.1
 +
  netmask 255.255.255.0
 +
  broadcast 192.168.2.255
 +
  post-up /etc/network/fwmark_rules</pre>
  
I used these guides to write complete this:
+
== /etc/sysctl.d/local.conf ==
 +
If you want to use fwmark rules you need to change this setting. It causes the router to still do source validation.
 +
 
 +
<pre># Needed to use fwmark
 +
net.ipv4.conf.all.rp_filter = 2
 +
</pre>
  
* [http://nerdboys.com/2006/05/05/conning-the-mark-multiwan-connections-using-iptables-mark-connmark-and-iproute2 Conning the Mark: Multiwan connections using IPTables, MARK, CONNMARK and iproute2 ]
+
fwmark won't work if you have this set to 1.
* [http://nerdboys.com/2006/05/08/multiwan-connections-addendum Multiwan connections addendum]
 
* [http://inai.de/images/nf-packet-flow.png Netfilter packet flow]
 
  
<pre>#########################################################################
+
== /etc/network/fwmark_rules ==
# Advanced routing rule set
+
In this file we want to put the fwmark rules and set the correct priorities.
# Uses 192.168.1.0 via ISP
 
#      192.168.2.0 via VPN
 
#
 
# Packets to/from 192.168.1.0/24 are marked with 0x1 and routed to ISP
 
# Packets to/from 192.168.2.0/24 are marked with 0x2 and routed to VPN
 
#
 
#########################################################################
 
  
#
+
<pre>#!/bin/sh
# NAT Table
 
# This is where translation of packets happens and "forwarding" of ports
 
# to specific hosts.
 
#
 
*nat
 
  
# Set default policies for table
+
# Normal packets to go direct out WAN
:PREROUTING ACCEPT [0:0]
+
/sbin/ip rule add fwmark 1 table ISP prio 100
:INPUT ACCEPT [0:0]
 
:OUTPUT ACCEPT [0:0]
 
:POSTROUTING ACCEPT [0:0]
 
  
# Port forwarding for Bittorrent
+
# Put packets destined into VPN when VPN is up
-A PREROUTING -i tun0 -p tcp -m tcp --dport 6881:6889 -j DNAT --to-destination 192.168.2.20
+
/sbin/ip rule add fwmark 2 table VPN prio 200
-A PREROUTING -i tun0 -p udp -m udp --dport 6881:6889 -j DNAT --to-destination 192.168.2.20
 
  
# Allows routing to our modem subnet so we can access the web interface
+
# Prevent packets from being routed out when VPN is down.
-A POSTROUTING -s 192.168.1.0/24 -d 192.168.0.1/32 -o eth1 -p tcp -m tcp --dport 80 -j MASQUERADE
+
# This prevents packets from falling back to the main table
-A POSTROUTING -s 192.168.2.0/24 -d 192.168.0.1/32 -o eth1 -p tcp -m tcp --dport 80 -j MASQUERADE
+
# that has a priority of 32766
 +
/sbin/ip rule add prohibit fwmark 2 prio 300</pre>
  
# Allows hosts of the network to use the VPN tunnel
+
== /etc/ppp/ip-up ==
-A POSTROUTING -o tun0 -j MASQUERADE
+
Next up we want to create the routes that should be run when PPP comes online. There are special hooks we can use in ip-up and ip-down to refer to the IP address, [https://ppp.samba.org/pppd.html#sect13 ppp man file - Scripts ] You can also read about them in your man file if you have ppp-doc installed.
 
 
# Allows hosts of the network to use the PPP tunnel
 
-A POSTROUTING -o ppp0 -j MASQUERADE
 
COMMIT
 
  
 +
<pre>#!/bin/sh
 
#
 
#
# Filter Table
+
# This script is run by pppd when there's a successful ppp connection.
# This is where we decide to ACCEPT, DROP or REJECT things
 
 
#
 
#
*filter
 
:INPUT DROP [0:0]
 
:FORWARD DROP [0:0]
 
:OUTPUT ACCEPT [0:0]
 
  
# Create rule chain per input interface for forwarding packets
+
# Flush out any old rules that might be there
:FWD_ETH0 - [0:0]
+
/sbin/ip route flush table ISP
:FWD_ETH1 - [0:0]
+
 
:FWD_PPP0 - [0:0]
+
# Add route to table from subnets on LAN
:FWD_TUN0 - [0:0]
+
/sbin/ip route add 192.168.1.0/24 dev eth0 table ISP
 +
/sbin/ip route add 192.168.2.0/24 dev eth0 table ISP
  
# Create rule chain per input interface for input packets (for host itself)
+
# Add route from IP given by ISP to the table
:IN_ETH0 - [0:0]
+
/sbin/ip rule add from ${IPREMOTE} table ISP prio 100
:IN_ETH1 - [0:0]
 
:IN_PPP0 - [0:0]
 
:IN_TUN0 - [0:0]
 
  
# Create a log drop chain
+
# Add a default route
:LOG_DROP - [0:0]
+
/sbin/ip route add table ISP default via ${IPREMOTE} dev ${IFNAME}</pre>
  
# Create a reject chain
+
== /etc/ppp/ip-down ==
:LOG_REJECT - [0:0]
+
<pre>#!/bin/sh
 +
#
 +
# This script is run by pppd after the connection has ended.
 +
#
  
# Pass input packet to corresponding rule chain
+
# Delete the rules when we take the interface down
-A INPUT -i lo -j ACCEPT
+
/sbin/ip rule del from ${IPREMOTE} table ISP prio 100</pre>
-A INPUT -i eth0 -j IN_ETH0
 
-A INPUT -i eth1 -j IN_ETH1
 
-A INPUT -i ppp0 -j IN_PPP0
 
-A INPUT -i tun0 -j IN_TUN0
 
  
# Track forwarded packets
+
== /etc/openvpn/route-up-fwmark.sh ==
-A FORWARD -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT
+
OpenVPN needs similar routing scripts and it also has it's own special hooks that allow you to specify particular values. A full list is here [https://openvpn.net/index.php/open-source/documentation/manuals/65-openvpn-20x-manpage.html#lbAS OpenVPN man file - Environmental Variables]
  
# Pass forwarded packet to corresponding rule chain
+
<pre>#!/bin/sh
-A FORWARD -i eth0 -j FWD_ETH0
+
#
-A FORWARD -i eth1 -j FWD_ETH1
+
# This script is run by OpenVPN when there's a successful VPN connection.
-A FORWARD -i ppp0 -j FWD_PPP0
+
#
-A FORWARD -i tun0 -j FWD_TUN0
 
  
# Forward traffic to ISP
+
# Flush out any old rules that might be there
-A FWD_ETH0 -s 192.168.1.0/24 -j ACCEPT
+
/sbin/ip route flush table VPN
  
# Forward traffic to VPN
+
# Add route to table from 192.168.2.0/24 subnet on LAN
-A FWD_ETH0 -s 192.168.2.0/24 -j ACCEPT
+
/sbin/ip route add 192.168.2.0/24 dev eth0 table VPN
  
# Allow excepted server to be FORWARD to ppp0
+
# Add route from VPN interface IP to the VPN table
#-A FWD_ETH0 -s 192.168.2.0/24 -d <IP_OF_EXCEPTED_SERVER>/32 -o ppp0 -j ACCEPT
+
/sbin/ip rule add from ${ifconfig_local} table VPN prio 200
  
# Forward SSH packets from network to modem
+
# Add a default route
-A FWD_ETH1 -s 192.168.0.1/32 -d 192.168.1.0/24 -p tcp -m tcp --sport 22 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
+
/sbin/ip route add default via ${ifconfig_local} dev ${dev} table VPN</pre>
-A FWD_ETH1 -s 192.168.0.1/32 -d 192.168.2.0/24 -p tcp -m tcp --sport 22 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
 
  
# Forward HTTP packets from network to modem
+
== /etc/openvpn/route-pre-down-fwmark.sh ==
-A FWD_ETH1 -s 192.168.0.1/32 -d 192.168.1.0/24 -p tcp -m tcp --sport 80 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
 
-A FWD_ETH1 -s 192.168.0.1/32 -d 192.168.2.0/24 -p tcp -m tcp --sport 80 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
 
  
# Forward Bittorrent Port to workstation
+
<pre>#!/bin/sh
-A FWD_TUN0 -d 192.168.2.20/32 -p tcp -m tcp --dport 6881:6889 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
+
#
-A FWD_TUN0 -d 192.168.2.20/32 -p udp -m udp --dport 6881:6889 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
+
# This script is run by OpenVPN after the connection has ended
 +
#
  
# SSH to Router
+
# Delete the rules when we take the interface down
-A IN_ETH0 -s 192.168.1.0/24 -p tcp -m tcp --dport 22 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
+
/sbin/ip rule del from ${ifconfig_local} table VPN prio 200</pre>
-A IN_ETH0 -s 192.168.2.0/24 -p tcp -m tcp --dport 22 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
 
  
# DNS to Router
+
What I did find was when starting and stopping the OpenVPN service if you used:
-A IN_ETH0 -s 192.168.1.0/24 -p udp -m udp --dport 53 -m conntrack --ctstate NEW -j ACCEPT
 
-A IN_ETH0 -s 192.168.2.0/24 -p udp -m udp --dport 53 -m conntrack --ctstate NEW -j ACCEPT
 
  
# FreeRadius Client (eg a UniFi AP)
+
{{cmd|service openvpn stop}}
-A IN_ETH0 -s 192.168.1.0/24 -p tcp -m tcp --dport 1812 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
 
-A IN_ETH0 -s 192.168.1.0/24 -p udp -m udp --dport 1812 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
 
  
# Ubiquiti UAP Device Discovery Broadcast
+
The rules in route-pre-down-fwmark.sh were not executed.
-A IN_ETH0 -s 192.168.1.0/24 -p udp -m udp --dport 10001 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
 
  
# NTP to Router
+
However:
-A IN_ETH0 -s 192.168.1.0/24 -p udp -m udp --dport 123 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
 
-A IN_ETH0 -s 192.168.2.0/24 -p udp -m udp --dport 123 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
 
  
# Accept traffic to router on both subnets
+
{{cmd|/etc/init.d/openvpn stop}}
-A IN_ETH0 -s 192.168.1.0/24 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
 
-A IN_ETH0 -s 192.168.2.0/24 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
 
  
# Allow excepted server to be INPUT to eth0 from LAN
+
seemed to work correctly.
#-A IN_ETH0 -s 192.168.2.0/24 -d <IP_OF_EXCEPTED_SERVER>/32 -o ppp0 -j ACCEPT
 
  
# SSH To Modem from Router
+
== Advanced IPtables rules that allow us to route into our two routing tables ==
-A IN_ETH1 -s 192.168.0.1/32 -d 192.168.0.0/30 -p tcp -m tcp --sport 22 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
+
This is an expansion of the previous set of rules. It sets up NAT masquerading for the 192.168.2.0 to go through the VPN using marked packets.
  
# HTTP To Modem from Router
+
I used these guides to write complete this:
-A IN_ETH1 -s 192.168.0.1/32 -d 192.168.0.0/30 -p tcp -m tcp --sport 80 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
 
  
# Accept incoming tracked PPP0 connection
+
* [http://nerdboys.com/2006/05/05/conning-the-mark-multiwan-connections-using-iptables-mark-connmark-and-iproute2 Conning the Mark: Multiwan connections using IPTables, MARK, CONNMARK and iproute2 ]
-A IN_PPP0 -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT
+
* [http://nerdboys.com/2006/05/08/multiwan-connections-addendum Multiwan connections addendum]
 
+
* [http://inai.de/images/nf-packet-flow.png Netfilter packet flow]
# Log dropped packets coming in on PPP0
 
-A IN_PPP0 -j LOG --log-prefix "DROP:INPUT " --log-level 6
 
-A IN_PPP0 -j LOG_DROP
 
 
 
# Accept incoming tracked TUN0 connection
 
-A IN_TUN0 -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT
 
 
 
# Log dropped packets coming in on TUN0
 
-A IN_TUN0 -j LOG --log-prefix "DROP:INPUT " --log-level 6
 
-A IN_TUN0 -j LOG_DROP
 
COMMIT
 
  
 +
<pre>#########################################################################
 +
# Advanced routing rule set
 +
# Uses 192.168.1.0 via ISP
 +
#      192.168.2.0 via VPN
 
#
 
#
# Mangle Table
+
# Packets to/from 192.168.1.0/24 are marked with 0x1 and routed to ISP
# This is the place where our markings happen, whether they be 0x1 or 0x2
+
# Packets to/from 192.168.2.0/24 are marked with 0x2 and routed to VPN
 
#
 
#
*mangle
+
#########################################################################
  
# Set default policies for table
+
#
 +
# NAT Table
 +
# This is where translation of packets happens and "forwarding" of ports
 +
# to specific hosts.
 +
#
 +
*nat
 +
 
 +
# Set default policies for table
 
:PREROUTING ACCEPT [0:0]
 
:PREROUTING ACCEPT [0:0]
 
:INPUT ACCEPT [0:0]
 
:INPUT ACCEPT [0:0]
:FORWARD ACCEPT [0:0]
 
 
:OUTPUT ACCEPT [0:0]
 
:OUTPUT ACCEPT [0:0]
 
:POSTROUTING ACCEPT [0:0]
 
:POSTROUTING ACCEPT [0:0]
  
# Restore CONNMARK to the MARK (If one doesn't exist then no mark is set)
+
# Port forwarding for Bittorrent
-A PREROUTING -j CONNMARK --restore-mark --nfmask 0xffffffff --ctmask 0xffffffff
+
-A PREROUTING -i tun0 -p tcp -m tcp --dport 6881:6889 -j DNAT --to-destination 192.168.2.20
 +
-A PREROUTING -i tun0 -p udp -m udp --dport 6881:6889 -j DNAT --to-destination 192.168.2.20
  
# If packet MARK is 2, then it means there is already a connection mark and the
+
# Allows routing to our modem subnet so we can access the web interface
# original packet came in on VPN
+
-A POSTROUTING -s 192.168.1.0/24 -d 192.168.0.1/32 -o eth1 -p tcp -m tcp --dport 80 -j MASQUERADE
-A PREROUTING -s 192.168.2.0/24 -m mark --mark 0x2 -j ACCEPT
+
-A POSTROUTING -s 192.168.2.0/24 -d 192.168.0.1/32 -o eth1 -p tcp -m tcp --dport 80 -j MASQUERADE
  
# Check exception (this is a server which when accessed on a 192.168.2.0/24 address will go out the ISP table) are 0x1
+
# Allows hosts of the network to use the VPN tunnel
#-A PREROUTING -s 192.168.2.0/24 -d <IP_OF_EXCEPTED_SERVER>/32 -m mark --mark 0x1 -j ACCEPT
+
-A POSTROUTING -o tun0 -j MASQUERADE
  
# Mark packets coming from 192.168.2.0/24 are 0x2
+
# Allows hosts of the network to use the PPP tunnel
-A PREROUTING -s 192.168.2.0/24 -j MARK --set-xmark 0x2/0xffffffff
+
-A POSTROUTING -o ppp0 -j MASQUERADE
 +
COMMIT
  
# If packet MARK is 1, then it means there is already a connection mark and the
+
#
# original packet came in on ISP
+
# Filter Table
-A PREROUTING -s 192.168.1.0/24 -m mark --mark 0x1 -j ACCEPT
+
# This is where we decide to ACCEPT, DROP or REJECT things
 +
#
 +
*filter
 +
:INPUT DROP [0:0]
 +
:FORWARD DROP [0:0]
 +
:OUTPUT ACCEPT [0:0]
  
# Mark packets 192.168.1.0/24 are 0x1
+
# Create rule chain per input interface for forwarding packets
-A PREROUTING -s 192.168.1.0/24 -j MARK --set-xmark 0x1/0xffffffff
+
:FWD_ETH0 - [0:0]
 +
:FWD_ETH1 - [0:0]
 +
:FWD_PPP0 - [0:0]
 +
:FWD_TUN0 - [0:0]
  
# Mark exception (this is a server which when accessed on a 192.168.2.0/24 address will go out the ISP table) as 0x1
+
# Create rule chain per input interface for input packets (for host itself)
#-A PREROUTING -s 192.168.2.0/24 -d <IP_OF_EXCEPTED_SERVER>/32 -j MARK --set-xmark 0x1/0xffffffff
+
:IN_ETH0 - [0:0]
 +
:IN_ETH1 - [0:0]
 +
:IN_PPP0 - [0:0]
 +
:IN_TUN0 - [0:0]
  
# Set mark to 0 - This is for the modem. Otherwise it will mark with 0x1 or 0x2
+
# Create a log drop chain
-A PREROUTING -d 192.168.0.1/32 -j MARK --set-xmark 0x0/0xffffffff
+
:LOG_DROP - [0:0]
  
# Save MARK to CONNMARK (remember iproute can't see CONNMARKs)
+
# Create a reject chain
-A PREROUTING -j CONNMARK --save-mark --nfmask 0xffffffff --ctmask 0xffffffff
+
:LOG_REJECT - [0:0]
COMMIT</pre>
 
  
You may want to delete certain rules here that do not apply to you, eg the FreeRadius rules. That is covered later in this article.
+
# Pass input packet to corresponding rule chain
 +
-A INPUT -i lo -j ACCEPT
 +
-A INPUT -i eth0 -j IN_ETH0
 +
-A INPUT -i eth1 -j IN_ETH1
 +
-A INPUT -i ppp0 -j IN_PPP0
 +
-A INPUT -i tun0 -j IN_TUN0
  
== OpenVPN Routing ==
+
# Track forwarded packets
Usually when you connect with OpenVPN the remote VPN server will push routes down to your system. We don't want this as we still want to be able to access the internet without the VPN. We have also created our own routes that we want to use earlier in this guide.
+
-A FORWARD -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT
  
You'll need to add this to the bottom of your OpenVPN configuration file:
+
# Pass forwarded packet to corresponding rule chain
<pre># Prevents default gateway from being set on the default routing table
+
-A FORWARD -i eth0 -j FWD_ETH0
route-noexec
+
-A FORWARD -i eth1 -j FWD_ETH1
 +
-A FORWARD -i ppp0 -j FWD_PPP0
 +
-A FORWARD -i tun0 -j FWD_TUN0
  
# Allows route-up script to be executed
+
# Forward traffic to ISP
script-security 2
+
-A FWD_ETH0 -s 192.168.1.0/24 -j ACCEPT
  
# Calls custom shell script after connection to add necessary routes
+
# Forward traffic to VPN
route-up /etc/openvpn/route-up-fwmark.sh
+
-A FWD_ETH0 -s 192.168.2.0/24 -j ACCEPT
route-pre-down /etc/openvpn/route-pre-down-fwmark.sh</pre>
 
  
My VPNs are arranged like this in /etc/openvpn:
+
# Allow excepted server to be FORWARD to ppp0
 +
#-A FWD_ETH0 -s 192.168.2.0/24 -d <IP_OF_EXCEPTED_SERVER>/32 -o ppp0 -j ACCEPT
  
OpenVPN configuration file for that server:
+
# Forward SSH packets from network to modem
<pre>countrycode.serverNumber.openvpn.conf</pre>
+
-A FWD_ETH1 -s 192.168.0.1/32 -d 192.168.1.0/24 -p tcp -m tcp --sport 22 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
 +
-A FWD_ETH1 -s 192.168.0.1/32 -d 192.168.2.0/24 -p tcp -m tcp --sport 22 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
  
OpenVPN certs for that server:
+
# Forward HTTP packets from network to modem
<pre>countrycode.serverNumber.openvpn/countrycode.serverNumber.openvpn.crt
+
-A FWD_ETH1 -s 192.168.0.1/32 -d 192.168.1.0/24 -p tcp -m tcp --sport 80 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
countrycode.serverNumber.openvpn/countrycode.serverNumber.openvpn.key
+
-A FWD_ETH1 -s 192.168.0.1/32 -d 192.168.2.0/24 -p tcp -m tcp --sport 80 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
countrycode.serverNumber.openvpn/myKey.crt
 
countrycode.serverNumber.openvpn/myKey.key</pre>
 
  
So I use this helpful script to automate the process of changing between servers:
+
# Forward Bittorrent Port to workstation
 +
-A FWD_TUN0 -d 192.168.2.20/32 -p tcp -m tcp --dport 6881:6889 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
 +
-A FWD_TUN0 -d 192.168.2.20/32 -p udp -m udp --dport 6881:6889 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
  
<pre>#!/bin/sh
+
# SSH to Router
 +
-A IN_ETH0 -s 192.168.1.0/24 -p tcp -m tcp --dport 22 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
 +
-A IN_ETH0 -s 192.168.2.0/24 -p tcp -m tcp --dport 22 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
  
vpn_server_filename=$1
+
# DNS to Router
 +
-A IN_ETH0 -s 192.168.1.0/24 -p udp -m udp --dport 53 -m conntrack --ctstate NEW -j ACCEPT
 +
-A IN_ETH0 -s 192.168.2.0/24 -p udp -m udp --dport 53 -m conntrack --ctstate NEW -j ACCEPT
  
rm /etc/openvpn/openvpn.conf
+
# FreeRadius Client (eg a UniFi AP)
ln -s $vpn_server_filename /etc/openvpn/openvpn.conf
+
-A IN_ETH0 -s 192.168.1.0/24 -p tcp -m tcp --dport 1812 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
chown -R openvpn:openvpn /etc/openvpn
+
-A IN_ETH0 -s 192.168.1.0/24 -p udp -m udp --dport 1812 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
chmod -R a=-rwx,u=+rX /etc/openvpn
 
chmod u=x /etc/openvpn/*.sh*
 
  
if grep -Fxq "#CustomStuffHere" openvpn.conf
+
# Ubiquiti UAP Device Discovery Broadcast
then
+
-A IN_ETH0 -s 192.168.1.0/24 -p udp -m udp --dport 10001 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
    echo "Not adding custom routes, this server has been used previously"
 
else
 
    echo "Adding custom route rules"
 
cat <<EOF >> /etc/openvpn/openvpn.conf
 
  
#CustomStuffHere
+
# NTP to Router
# Prevents default gateway from being set on the default routing table
+
-A IN_ETH0 -s 192.168.1.0/24 -p udp -m udp --dport 123 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
route-noexec
+
-A IN_ETH0 -s 192.168.2.0/24 -p udp -m udp --dport 123 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
  
# Allows route-up script to be executed
+
# Accept traffic to router on both subnets
script-security 2
+
-A IN_ETH0 -s 192.168.1.0/24 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
 +
-A IN_ETH0 -s 192.168.2.0/24 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
  
# Calls custom shell script after connection to add necessary routes
+
# Allow excepted server to be INPUT to eth0 from LAN
route-up /etc/openvpn/route-up-fwmark.sh
+
#-A IN_ETH0 -s 192.168.2.0/24 -d <IP_OF_EXCEPTED_SERVER>/32 -o ppp0 -j ACCEPT
route-pre-down /etc/openvpn/route-pre-down-fwmark.sh
 
  
# Logging of OpenVPN to file
+
# SSH To Modem from Router
#log /etc/openvpn/openvpn.log
+
-A IN_ETH1 -s 192.168.0.1/32 -d 192.168.0.0/30 -p tcp -m tcp --sport 22 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
EOF
 
  
fi
+
# HTTP To Modem from Router
echo "Remember to set BitTorrent port forward in vcp.ovpn.to control panel"</pre>
+
-A IN_ETH1 -s 192.168.0.1/32 -d 192.168.0.0/30 -p tcp -m tcp --sport 80 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
  
That way I can simply change between servers by running:
+
# Accept incoming tracked PPP0 connection
{{cmd|changevpn.sh countrycode.serverNumber.openvpn}}
+
-A IN_PPP0 -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT
  
and then restart openvpn. I am also reminded to put the port forward through on the VPN control panel so my BitTorrent client is connectable:
+
# Log dropped packets coming in on PPP0
 +
-A IN_PPP0 -j LOG --log-prefix "DROP:INPUT " --log-level 6
 +
-A IN_PPP0 -j LOG_DROP
  
{{cmd|service openvpn restart}}
+
# Accept incoming tracked TUN0 connection
 +
-A IN_TUN0 -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT
  
Finally add openvpn to the default run level
+
# Log dropped packets coming in on TUN0
{{cmd|rc-update add openvpn default}}
+
-A IN_TUN0 -j LOG --log-prefix "DROP:INPUT " --log-level 6
 +
-A IN_TUN0 -j LOG_DROP
 +
COMMIT
  
= Creating a LAN only Subnet =
+
#
In this section, we'll be creating a LAN only subnet. This subnet will be 192.168.3.0/24. The idea of this subnet is nodes in it cannot have their packets forwarded to the Internet, however they can be accessed via the other LAN subnets 192.168.1.0/24 and 192.168.2.0/24. This approach doesn't use VLANs although that would be recommended if you had a managed switch. The idea of this subnet is for things like WiFi access points, IP Phones which contact a local Asterisk server and of course printers.
+
# Mangle Table
 +
# This is the place where our markings happen, whether they be 0x1 or 0x2
 +
#
 +
*mangle
  
At the end of this section we will have something like:
+
# Set default policies for table
 +
:PREROUTING ACCEPT [0:0]
 +
:INPUT ACCEPT [0:0]
 +
:FORWARD ACCEPT [0:0]
 +
:OUTPUT ACCEPT [0:0]
 +
:POSTROUTING ACCEPT [0:0]
  
[[File:Network diagram ipv4 tunnel LANONLY ROUTE.svg|900px|center|Network Diagram LAN ONLY Route with IPv4]]
+
# Restore CONNMARK to the MARK (If one doesn't exist then no mark is set)
 +
-A PREROUTING -j CONNMARK --restore-mark --nfmask 0xffffffff --ctmask 0xffffffff
  
== /etc/iproute2/rt_tables ==
+
# If packet MARK is 2, then it means there is already a connection mark and the
First up we'll add a third routing table:
+
# original packet came in on VPN
 +
-A PREROUTING -s 192.168.2.0/24 -m mark --mark 0x2 -j ACCEPT
  
<pre>3 LAN</pre>
+
# Check exception (this is a server which when accessed on a 192.168.2.0/24 address will go out the ISP table) are 0x1
 +
#-A PREROUTING -s 192.168.2.0/24 -d <IP_OF_EXCEPTED_SERVER>/32 -m mark --mark 0x1 -j ACCEPT
  
== /etc/network/interfaces ==
+
# Mark packets coming from 192.168.2.0/24 are 0x2
Add a an extra virtual interface (really just a IP address to eth0).
+
-A PREROUTING -s 192.168.2.0/24 -j MARK --set-xmark 0x2/0xffffffff
  
<pre># LAN Only
+
# If packet MARK is 1, then it means there is already a connection mark and the
auto eth0:3
+
# original packet came in on ISP
iface eth0:3 inet static
+
-A PREROUTING -s 192.168.1.0/24 -m mark --mark 0x1 -j ACCEPT
  address 192.168.3.1
 
  netmask 255.255.255.0
 
  broadcast 192.168.3.255
 
  post-up /etc/network/route_LAN</pre>
 
  
== /etc/network/route_LAN ==
+
# Mark packets 192.168.1.0/24 are 0x1
This file will have our route added to it
+
-A PREROUTING -s 192.168.1.0/24 -j MARK --set-xmark 0x1/0xffffffff
  
<pre>#!/bin/sh
+
# Mark exception (this is a server which when accessed on a 192.168.2.0/24 address will go out the ISP table) as 0x1
 +
#-A PREROUTING -s 192.168.2.0/24 -d <IP_OF_EXCEPTED_SERVER>/32 -j MARK --set-xmark 0x1/0xffffffff
  
# Add routes from ISP to LAN
+
# Set mark to 0 - This is for the modem. Otherwise it will mark with 0x1 or 0x2
/sbin/ip route add 192.168.1.0/24 dev eth0 table LAN
+
-A PREROUTING -d 192.168.0.1/32 -j MARK --set-xmark 0x0/0xffffffff
  
# Add route from VPN to LAN
+
# Save MARK to CONNMARK (remember iproute can't see CONNMARKs)
/sbin/ip route add 192.168.2.0/24 dev eth0 table LAN
+
-A PREROUTING -j CONNMARK --save-mark --nfmask 0xffffffff --ctmask 0xffffffff
 +
COMMIT</pre>
  
# Add route from LAN to it's own table
+
You may want to delete certain rules here that do not apply to you, eg the FreeRadius rules. That is covered later in this article.
/sbin/ip route add 192.168.3.0/24 dev eth0 table LAN</pre>
 
  
== /etc/ppp/ip-up ==
+
== OpenVPN Routing ==
Append a route from the LAN subnet to the ISP table
+
Usually when you connect with OpenVPN the remote VPN server will push routes down to your system. We don't want this as we still want to be able to access the internet without the VPN. We have also created our own routes that we want to use earlier in this guide.
  
<pre># Add route to LAN subnet
+
You'll need to add this to the bottom of your OpenVPN configuration file:
/sbin/ip route add 192.168.3.0/24 dev eth0 table ISP</pre>
+
<pre># Prevents default gateway from being set on the default routing table
 +
route-noexec
  
== /etc/openvpn/route-up-fwmark.sh ==
+
# Allows route-up script to be executed
Append a route from the LAN subnet to the VPN table
+
script-security 2
  
<pre># Add route to LAN only subnet
+
# Calls custom shell script after connection to add necessary routes
/sbin/ip route add 192.168.3.0/24 dev eth0 table VPN</pre>
+
route-up /etc/openvpn/route-up-fwmark.sh
 +
route-pre-down /etc/openvpn/route-pre-down-fwmark.sh</pre>
  
== /etc/ntpd.conf ==
+
My VPNs are arranged like this in /etc/openvpn:
Add a listen address for ntp (OpenNTPD).
 
  
You should now have:
+
OpenVPN configuration file for that server:
 +
<pre>countrycode.serverNumber.openvpn.conf</pre>
  
<pre># Addresses to listen on (ntpd does not listen by default)
+
OpenVPN certs for that server:
listen on 192.168.1.1
+
<pre>countrycode.serverNumber.openvpn/countrycode.serverNumber.openvpn.crt
listen on 192.168.2.1
+
countrycode.serverNumber.openvpn/countrycode.serverNumber.openvpn.key
listen on 192.168.3.1</pre>
+
countrycode.serverNumber.openvpn/myKey.crt
 +
countrycode.serverNumber.openvpn/myKey.key</pre>
  
Devices needing the correct time will need to use this NTP server because they will not be able to get it from the Internet.
+
So I use this helpful script to automate the process of changing between servers:
  
== Blocking bogons ==
+
<pre>#!/bin/sh
Our LAN now has 4 subnets in total that are possible:
 
  
* 192.168.0.0/30 (connection between modem and router)
+
vpn_server_filename=$1
* 192.168.1.0/24 (ISP table, directly routed out WAN)
 
* 192.168.2.0/24 (VPN table, routed out VPN)
 
* 192.168.3.0/24 (Null routed subnet for LAN only hosts)
 
* 172.16.32.0/20 (VPN provider's network, so we can access things on the VPN's network).
 
  
Everything else should be rejected. No packets should ever be forwarded on 192.168.5.2 or 10.0.0.5 for example.
+
rm /etc/openvpn/openvpn.conf
 +
ln -s $vpn_server_filename /etc/openvpn/openvpn.conf
 +
chown -R openvpn:openvpn /etc/openvpn
 +
chmod -R a=-rwx,u=+rX /etc/openvpn
 +
chmod u=x /etc/openvpn/*.sh*
  
=== Installing ipset ===
+
if grep -Fxq "#CustomStuffHere" openvpn.conf
Install ipset:
+
then
 +
    echo "Not adding custom routes, this server has been used previously"
 +
else
 +
    echo "Adding custom route rules"
 +
cat <<EOF >> /etc/openvpn/openvpn.conf
  
{{cmd|apk add ipset}}
+
#CustomStuffHere
 +
# Prevents default gateway from being set on the default routing table
 +
route-noexec
 +
 
 +
# Allows route-up script to be executed
 +
script-security 2
 +
 
 +
# Calls custom shell script after connection to add necessary routes
 +
route-up /etc/openvpn/route-up-fwmark.sh
 +
route-pre-down /etc/openvpn/route-pre-down-fwmark.sh
 +
 
 +
# Logging of OpenVPN to file
 +
#log /etc/openvpn/openvpn.log
 +
EOF
  
Add it to start up:
+
fi
{{cmd|rc-update add ipset default}}
+
echo "Remember to set BitTorrent port forward in VPN control panel"</pre>
  
Now we need to load the lists of addresses into ipset [http://blog.ls20.com/securing-your-server-using-ipset-and-dynamic-blocklists Securing Your Server using IPset and Dynamic Blocklists] mentions a [https://gist.github.com/hwdsl2/6dce75072274abfd2781 script] which was particularly useful. This script could be run on a cron job if you wanted to regularly update it and for the full bogon list you should as they change when that address space has been allocated.
+
That way I can simply change between servers by running:
 +
{{cmd|changevpn.sh countrycode.serverNumber.openvpn}}
  
For the purpose of this we will be using just the [https://files.pfsense.org/lists/bogon-bn-nonagg.txt bogon-bn-nonagg.txt] list.
+
and then restart openvpn. I am also reminded to put the port forward through on the VPN control panel so my BitTorrent client is connectable:
  
<pre>0.0.0.0/8
+
{{cmd|service openvpn restart}}
10.0.0.0/8
 
100.64.0.0/10
 
127.0.0.0/8
 
169.254.0.0/16
 
172.16.0.0/12
 
192.0.0.0/24
 
192.0.2.0/24
 
192.168.0.0/16
 
198.18.0.0/15
 
198.51.100.0/24
 
203.0.113.0/24
 
224.0.0.0/4
 
240.0.0.0/4</pre>
 
  
This is unlikely to change as it's the IPV4 [https://en.wikipedia.org/wiki/Reserved_IP_addresses Reserved IP addresses] space. The script:
+
Finally add openvpn to the default run level
 +
{{cmd|rc-update add openvpn default}}
  
<pre>#! /bin/bash
+
= Creating a LAN only Subnet =
 +
In this section, we'll be creating a LAN only subnet. This subnet will be 192.168.3.0/24. The idea of this subnet is nodes in it cannot have their packets forwarded to the Internet, however they can be accessed via the other LAN subnets 192.168.1.0/24 and 192.168.2.0/24. This approach doesn't use VLANs although that would be recommended if you had a managed switch. The idea of this subnet is for things like WiFi access points, IP Phones which contact a local Asterisk server and of course printers.
  
# /usr/local/sbin/fullbogons-ipv4
+
At the end of this section we will have something like:
# BoneKracker
 
# Rev. 11 October 2012
 
# Tested with ipset 6.13
 
  
# Purpose: Periodically update an ipset used in a running firewall to block
+
[[File:Network diagram ipv4 tunnel LANONLY ROUTE.svg|900px|center|Network Diagram LAN ONLY Route with IPv4]]
# bogons. Bogons are addresses that nobody should be using on the public
 
# Internet because they are either private, not to be assigned, or have
 
# not yet been assigned.
 
#
 
# Notes: Call this from crontab. Feed updated every 4 hours.
 
  
# target="http://www.team-cymru.org/Services/Bogons/fullbogons-ipv4.txt"
+
== /etc/iproute2/rt_tables ==
# Use alternative URL from pfSense, due to 404 error with URL above
+
First up we'll add a third routing table:
target="https://files.pfsense.org/lists/bogon-bn-nonagg.txt"
 
ipset_params="hash:net"
 
  
filename=$(basename ${target})
+
<pre>3 LAN</pre>
firewall_ipset=${filename%.*}          # ipset will be filename minus ext
 
data_dir="/var/tmp/${firewall_ipset}"  # data directory will be same
 
data_file="${data_dir}/${filename}"
 
  
# if data directory does not exist, create it
+
== /etc/network/interfaces ==
mkdir -pm 0750 ${data_dir}
+
Add a an extra virtual interface (really just a IP address to eth0).
  
# function to get modification time of the file in log-friendly format
+
<pre># LAN Only
get_timestamp() {
+
auto eth0:3
    date -r $1 +%m/%d' '%R
+
iface eth0:3 inet static
}
+
  address 192.168.3.1
 +
  netmask 255.255.255.0
 +
  broadcast 192.168.3.255
 +
  post-up /etc/network/route_LAN</pre>
  
# file modification time on server is preserved during wget download
+
== /etc/network/route_LAN ==
[ -w ${data_file} ] && old_timestamp=$(get_timestamp ${data_file})
+
This file will have our route added to it
  
# fetch file only if newer than the version we already have
+
<pre>#!/bin/sh
wget -qNP ${data_dir} ${target}
 
  
if [ "$?" -ne "0" ]; then
+
# Add routes from ISP to LAN
    logger -p cron.err "IPSet: ${firewall_ipset} wget failed."
+
/sbin/ip route add 192.168.1.0/24 dev eth0 table LAN
    exit 1
 
fi
 
  
timestamp=$(get_timestamp ${data_file})
+
# Add route from VPN to LAN
 +
/sbin/ip route add 192.168.2.0/24 dev eth0 table LAN
  
# compare timestamps because wget returns success even if no newer file
+
# Add route from LAN to it's own table
if [ "${timestamp}" != "${old_timestamp}" ]; then
+
/sbin/ip route add 192.168.3.0/24 dev eth0 table LAN</pre>
  
    temp_ipset="${firewall_ipset}_temp"
+
== /etc/ppp/ip-up ==
    ipset create ${temp_ipset} ${ipset_params}
+
Append a route from the LAN subnet to the ISP table
  
    #sed -i '/^#/d' ${data_file}            # strip comments
+
<pre># Add route to LAN subnet
    sed -ri '/^[#< \t]|^$/d' ${data_file}  # occasionally the file has been xhtml
+
/sbin/ip route add 192.168.3.0/24 dev eth0 table ISP</pre>
  
    while read network; do
+
== /etc/openvpn/route-up-fwmark.sh ==
        ipset add ${temp_ipset} ${network}
+
Append a route from the LAN subnet to the VPN table
    done < ${data_file}
 
  
    # if ipset does not exist, create it
+
<pre># Add route to LAN only subnet
    ipset create -exist ${firewall_ipset} ${ipset_params}
+
/sbin/ip route add 192.168.3.0/24 dev eth0 table VPN</pre>
  
    # swap the temp ipset for the live one
+
== /etc/ntpd.conf ==
    ipset swap ${temp_ipset} ${firewall_ipset}
+
Add a listen address for ntp (OpenNTPD).
    ipset destroy ${temp_ipset}
 
  
    # log the file modification time for use in minimizing lag in cron schedule
+
You should now have:
    logger -p cron.notice "IPSet: ${firewall_ipset} updated (as of: ${timestamp})."
 
  
fi</pre>
+
<pre># Addresses to listen on (ntpd does not listen by default)
 +
listen on 192.168.1.1
 +
listen on 192.168.2.1
 +
listen on 192.168.3.1</pre>
  
Now you should see the list loaded into memory when you do:
+
Devices needing the correct time will need to use this NTP server because they will not be able to get it from the Internet.
  
{{cmd|ipset list}}
+
== Blocking bogons ==
 +
Our LAN now has 4 subnets in total that are possible:
  
We want to save it so our router can refer to it next time it starts up so for that:
+
* 192.168.0.0/30 (connection between modem and router)
 +
* 192.168.1.0/24 (ISP table, directly routed out WAN)
 +
* 192.168.2.0/24 (VPN table, routed out VPN)
 +
* 192.168.3.0/24 (Null routed subnet for LAN only hosts)
 +
* 172.16.32.0/20 (VPN provider's network, so we can access things on the VPN's network).
  
{{cmd|/etc/init.d/ipset save}}
+
Everything else should be rejected. No packets should ever be forwarded on 192.168.5.2 or 10.0.0.5 for example.
  
=== Adding our allowed networks ===
+
=== Installing ipset ===
 +
Install ipset:
  
==== IPv4 ====
+
{{cmd|apk add ipset}}
{{cmd|ipset create allowed-nets-ipv4 hash:net,iface family inet}}
 
  
Then you can add each of your allowed networks:
+
Add it to start up:
 +
{{cmd|rc-update add ipset default}}
  
<pre>ipset add allowed-nets-ipv4 192.168.0.0/30,eth1
+
Now we need to load the lists of addresses into ipset [http://blog.ls20.com/securing-your-server-using-ipset-and-dynamic-blocklists Securing Your Server using IPset and Dynamic Blocklists] mentions a [https://gist.github.com/hwdsl2/6dce75072274abfd2781 script] which was particularly useful. This script could be run on a cron job if you wanted to regularly update it and for the full bogon list you should as they change when that address space has been allocated.
ipset add allowed-nets-ipv4 192.168.1.0/24,eth0
 
ipset add allowed-nets-ipv4 192.168.2.0/24,eth0
 
ipset add allowed-nets-ipv4 192.168.3.0/24,eth0
 
ipset add allowed-nets-ipv4 127.0.0.0/8,lo
 
ipset add allowed-nets-ipv4 172.16.32.0/20,tun0</pre>
 
  
==== IPv6 ====
+
For the purpose of this we will be using just the [https://files.pfsense.org/lists/bogon-bn-nonagg.txt bogon-bn-nonagg.txt] list.
For IPv6 if you've got any [https://en.wikipedia.org/wiki/Unique_local_address Unique local address] ranges you may choose to add them:
 
 
 
{{cmd|ipset create allowed-nets-ipv6 hash:net,iface family inet6}}
 
 
 
<pre>ipset add allowed-nets-ipv6 fde4:8dba:82e1::/48,tun0
 
ipset add allowed-nets-ipv6 fde4:8dba:82e1:ffff::/64,eth0</pre>
 
  
 +
<pre>0.0.0.0/8
 +
10.0.0.0/8
 +
100.64.0.0/10
 +
127.0.0.0/8
 +
169.254.0.0/16
 +
172.16.0.0/12
 +
192.0.0.0/24
 +
192.0.2.0/24
 +
192.168.0.0/16
 +
198.18.0.0/15
 +
198.51.100.0/24
 +
203.0.113.0/24
 +
224.0.0.0/4
 +
240.0.0.0/4</pre>
  
Finally save the sets with this command so they can be loaded next boot:
+
This is unlikely to change as it's the IPV4 [https://en.wikipedia.org/wiki/Reserved_IP_addresses Reserved IP addresses] space. The script:  
  
{{cmd|/etc/init.d/ipset save}}
+
<pre>#! /bin/bash
  
== Restricting our LAN subnet with iptables, and blocking the bogons ==
+
# /usr/local/sbin/fullbogons-ipv4
Finally we can apply our iptables rules, to filter both 192.168.3.0/24 and make sure that subnets like 192.168.5.0/24 are not forwarded or accessible by our router. You will need to review these rules, and remove the ones that do not apply to you.
+
# BoneKracker
 +
# Rev. 11 October 2012
 +
# Tested with ipset 6.13
  
Don't forget to change your RADIUS rules if you moved your WiFi APs into the 192.168.3.0/24 subnet. You'll also need to edit /etc/raddb/clients.conf
+
# Purpose: Periodically update an ipset used in a running firewall to block
 +
# bogons. Bogons are addresses that nobody should be using on the public
 +
# Internet because they are either private, not to be assigned, or have
 +
# not yet been assigned.
 +
#
 +
# Notes: Call this from crontab. Feed updated every 4 hours.
  
I used a new table here called "raw". This table is more primitive than the filter table. It cannot have FORWARD rules or INPUT rules. Therefore you will still need a FORWARD rule in your filter table to block bogons originating from your LAN.
+
# target="http://www.team-cymru.org/Services/Bogons/fullbogons-ipv4.txt"
 +
# Use alternative URL from pfSense, due to 404 error with URL above
 +
target="https://files.pfsense.org/lists/bogon-bn-nonagg.txt"
 +
ipset_params="hash:net"
  
The only kind of rules we may use here are PREROUTING and OUTPUT. The OUTPUT rules will only filter traffic originating from our router's local processes, such as if we ran the ping command to a bogon range on the router's command prompt.
+
filename=$(basename ${target})
 +
firewall_ipset=${filename%.*}          # ipset will be filename minus ext
 +
data_dir="/var/tmp/${firewall_ipset}"  # data directory will be same
 +
data_file="${data_dir}/${filename}"
  
Traffic passes over the raw table, before connecting marking as indicated by this packet flow map: [http://inai.de/images/nf-packet-flow.png Netfilter packet flow graph] this means we don't have to strip the mark off the bogon range in the mangle table anymore.
+
# if data directory does not exist, create it
 +
mkdir -pm 0750 ${data_dir}
  
<pre>#########################################################################
+
# function to get modification time of the file in log-friendly format
# Advanced routing rule set
+
get_timestamp() {
# Uses 192.168.1.0 via ISP
+
    date -r $1 +%m/%d' '%R
#      192.168.2.0 via VPN
+
}
#      192.168.3.0 via LAN
 
#
 
# Packets to/from 192.168.1.0/24 are marked with 0x1 and routed to ISP
 
# Packets to/from 192.168.2.0/24 are marked with 0x2 and routed to VPN
 
# Packets to/from 192.168.3.0/24 are routed to LAN and not forwarded onto
 
#                                    the internet
 
#
 
#########################################################################
 
  
#
+
# file modification time on server is preserved during wget download
# Raw Table
+
[ -w ${data_file} ] && old_timestamp=$(get_timestamp ${data_file})
# This table is the place where we drop all illegal packets from networks that
 
# do not exist
 
#
 
*raw
 
:PREROUTING ACCEPT [0:0]
 
:OUTPUT ACCEPT [0:0]
 
  
# Create a log drop chain
+
# fetch file only if newer than the version we already have
:LOG_DROP_BOGON - [0:0]
+
wget -qNP ${data_dir} ${target}
  
# Create an output chain
+
if [ "$?" -ne "0" ]; then
:OUT_PPP0 - [0:0]
+
    logger -p cron.err "IPSet: ${firewall_ipset} wget failed."
:OUT_TUN0 - [0:0]
+
    exit 1
 +
fi
  
# Allows traffic from VPN tunnel
+
timestamp=$(get_timestamp ${data_file})
-A PREROUTING -s 172.16.32.0/20 -i tun0 -j ACCEPT
 
  
# Allows traffic to VPN tunnel
+
# compare timestamps because wget returns success even if no newer file
-A PREROUTING -d 172.16.32.0/20 -j ACCEPT
+
if [ "${timestamp}" != "${old_timestamp}" ]; then
  
# Block specified bogons coming in from ISP and VPN
+
    temp_ipset="${firewall_ipset}_temp"
# (unlikely to happen as they filter them on their router)
+
    ipset create ${temp_ipset} ${ipset_params}
-A PREROUTING -i ppp0 -m set --match-set bogon-bn-nonagg src -j LOG_DROP_BOGON
 
-A PREROUTING -i tun0 -m set --match-set bogon-bn-nonagg src -j LOG_DROP_BOGON
 
  
# Allows my excepted ranges.
+
    #sed -i '/^#/d' ${data_file}            # strip comments
-A PREROUTING -m set --match-set allowed-nets-ipv4 src,src -j ACCEPT
+
    sed -ri '/^[#< \t]|^$/d' ${data_file}  # occasionally the file has been xhtml
  
# Pass output interface to corresponding chain
+
    while read network; do
-A OUTPUT -o ppp0 -j OUT_PPP0
+
        ipset add ${temp_ipset} ${network}
-A OUTPUT -o tun0 -j OUT_TUN0
+
    done < ${data_file}
  
# Log drop chain
+
    # if ipset does not exist, create it
-A LOG_DROP_BOGON -j LOG --log-prefix "Dropped Bogon (ipv4) : " --log-level 6
+
    ipset create -exist ${firewall_ipset} ${ipset_params}
-A LOG_DROP_BOGON -j DROP
 
  
# Block packets originating from the router destined to bogon ranges
+
    # swap the temp ipset for the live one
-A OUT_PPP0 -m set --match-set bogon-bn-nonagg dst -j LOG_DROP_BOGON
+
    ipset swap ${temp_ipset} ${firewall_ipset}
 +
    ipset destroy ${temp_ipset}
  
# Blocks packets originating from the router destined to bogon ranges
+
    # log the file modification time for use in minimizing lag in cron schedule
-A OUT_TUN0 -d 172.16.32.0/20 -j ACCEPT
+
    logger -p cron.notice "IPSet: ${firewall_ipset} updated (as of: ${timestamp})."
-A OUT_TUN0 -m set --match-set bogon-bn-nonagg dst -j LOG_DROP_BOGON
 
COMMIT
 
  
#
+
fi</pre>
# NAT Table
+
 
# This is where translation of packets happens and "forwarding" of ports
+
Now you should see the list loaded into memory when you do:
# to specific hosts.
 
#
 
*nat
 
:PREROUTING ACCEPT [0:0]
 
:INPUT ACCEPT [0:0]
 
:OUTPUT ACCEPT [0:0]
 
:POSTROUTING ACCEPT [0:0]
 
  
# Port forwarding for Bittorrent
+
{{cmd|ipset list}}
-A PREROUTING -i tun0 -p tcp -m tcp --dport 6881:6889 -j DNAT --to-destination 192.168.2.20
 
-A PREROUTING -i tun0 -p udp -m udp --dport 6881:6889 -j DNAT --to-destination 192.168.2.20
 
  
# Allows routing to our modem subnet so we can access the web interface
+
We want to save it so our router can refer to it next time it starts up so for that:
-A POSTROUTING -s 192.168.1.0/24 -d 192.168.0.1/32 -o eth1 -p tcp -m tcp --dport 80 -j MASQUERADE
 
-A POSTROUTING -s 192.168.2.0/24 -d 192.168.0.1/32 -o eth1 -p tcp -m tcp --dport 80 -j MASQUERADE
 
  
# Allows hosts of the network to use the VPN tunnel
+
{{cmd|/etc/init.d/ipset save}}
-A POSTROUTING -o tun0 -j MASQUERADE
 
  
# Allows hosts of the network to use the PPP tunnel
+
=== Adding our allowed networks ===
-A POSTROUTING -o ppp0 -j MASQUERADE
 
COMMIT
 
  
#
+
==== IPv4 ====
# Filter Table
+
{{cmd|ipset create allowed-nets-ipv4 hash:net,iface family inet}}
# This is where we decide to ACCEPT, DROP or REJECT things
 
#
 
*filter
 
:INPUT DROP [0:0]
 
:FORWARD DROP [0:0]
 
:OUTPUT ACCEPT [0:0]
 
  
# Create rule chain per input interface for forwarding packets
+
Then you can add each of your allowed networks:
:FWD_ETH0 - [0:0]
 
:FWD_ETH1 - [0:0]
 
:FWD_PPP0 - [0:0]
 
:FWD_TUN0 - [0:0]
 
  
# Create rule chain per input interface for input packets (for host itself)
+
<pre>ipset add allowed-nets-ipv4 192.168.0.0/30,eth1
:IN_ETH0 - [0:0]
+
ipset add allowed-nets-ipv4 192.168.1.0/24,eth0
:IN_ETH1 - [0:0]
+
ipset add allowed-nets-ipv4 192.168.2.0/24,eth0
:IN_PPP0 - [0:0]
+
ipset add allowed-nets-ipv4 192.168.3.0/24,eth0
:IN_TUN0 - [0:0]
+
ipset add allowed-nets-ipv4 127.0.0.0/8,lo
 +
ipset add allowed-nets-ipv4 172.16.32.0/20,tun0</pre>
  
# Create a drop chain
+
==== IPv6 ====
:LOG_DROP - [0:0]
+
For IPv6 if you've got any [https://en.wikipedia.org/wiki/Unique_local_address Unique local address] ranges you may choose to add them:
  
# Create a log drop chain
+
{{cmd|ipset create allowed-nets-ipv6 hash:net,iface family inet6}}
:LOG_DROP_BOGON - [0:0]
 
  
# Create a reject chain
+
<pre>ipset add allowed-nets-ipv6 fde4:8dba:82e1::/48,tun0
:LOG_REJECT_LANONLY - [0:0]
+
ipset add allowed-nets-ipv6 fde4:8dba:82e1:ffff::/64,eth0</pre>
  
# Create an output chain
 
:OUT_PPP0 - [0:0]
 
:OUT_TUN0 - [0:0]
 
  
# Pass input packet to corresponding rule chain
+
Finally save the sets with this command so they can be loaded next boot:
-A INPUT -i lo -j ACCEPT
 
-A INPUT -i eth0 -j IN_ETH0
 
-A INPUT -i eth1 -j IN_ETH1
 
-A INPUT -i ppp0 -j IN_PPP0
 
-A INPUT -i tun0 -j IN_TUN0
 
  
# Track forwarded packets
+
{{cmd|/etc/init.d/ipset save}}
-A FORWARD -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT
 
  
# Pass forwarded packet to corresponding rule chain
+
== Restricting our LAN subnet with iptables, and blocking the bogons ==
-A FORWARD -i eth0 -j FWD_ETH0
+
Finally we can apply our iptables rules, to filter both 192.168.3.0/24 and make sure that subnets like 192.168.5.0/24 are not forwarded or accessible by our router. You will need to review these rules, and remove the ones that do not apply to you.
-A FORWARD -i eth1 -j FWD_ETH1
 
-A FORWARD -i ppp0 -j FWD_PPP0
 
-A FORWARD -i tun0 -j FWD_TUN0
 
  
# Pass output interface to corresponding chain
+
Don't forget to change your RADIUS rules if you moved your WiFi APs into the 192.168.3.0/24 subnet. You'll also need to edit /etc/raddb/clients.conf
-A OUTPUT -o ppp0 -j OUT_PPP0
 
-A OUTPUT -o tun0 -j OUT_TUN0
 
  
# Forward traffic to Modem
+
I used a new table here called "raw". This table is more primitive than the filter table. It cannot have FORWARD rules or INPUT rules. Therefore you will still need a FORWARD rule in your filter table to block bogons originating from your LAN.
-A FWD_ETH0 -d 192.168.0.1/32 -j ACCEPT
 
  
# Allow routing to remote address on VPN
+
The only kind of rules we may use here are PREROUTING and OUTPUT. The OUTPUT rules will only filter traffic originating from our router's local processes, such as if we ran the ping command to a bogon range on the router's command prompt.
-A FWD_ETH0 -s 192.168.1.0/24 -d 172.16.32.1/32 -o tun0 -j ACCEPT
 
-A FWD_ETH0 -s 192.168.2.0/24 -d 172.16.32.1/32 -o tun0 -j ACCEPT
 
  
# Allow forwarding from LAN hosts to LAN ONLY subnet
+
Traffic passes over the raw table, before connecting marking as indicated by this packet flow map: [http://inai.de/images/nf-packet-flow.png Netfilter packet flow graph] this means we don't have to strip the mark off the bogon range in the mangle table anymore.
-A FWD_ETH0 -s 192.168.1.0/24 -d 192.168.3.0/24 -j ACCEPT
 
-A FWD_ETH0 -s 192.168.2.0/24 -d 192.168.3.0/24 -j ACCEPT
 
  
# Allow LAN ONLY subnet to contact other LAN hosts
+
<pre>#########################################################################
-A FWD_ETH0 -s 192.168.3.0/24 -d 192.168.1.0/24 -j ACCEPT
+
# Advanced routing rule set
-A FWD_ETH0 -s 192.168.3.0/24 -d 192.168.2.0/24 -j ACCEPT
+
# Uses 192.168.1.0 via ISP
 +
#      192.168.2.0 via VPN
 +
#      192.168.3.0 via LAN
 +
#
 +
# Packets to/from 192.168.1.0/24 are marked with 0x1 and routed to ISP
 +
# Packets to/from 192.168.2.0/24 are marked with 0x2 and routed to VPN
 +
# Packets to/from 192.168.3.0/24 are routed to LAN and not forwarded onto
 +
#                                    the internet
 +
#
 +
#########################################################################
  
# Refuse to forward bogons to the internet!
+
#
-A FWD_ETH0 -m set --match-set bogon-bn-nonagg dst -j LOG_DROP_BOGON
+
# Raw Table
 +
# This table is the place where we drop all illegal packets from networks that
 +
# do not exist
 +
#
 +
*raw
 +
:PREROUTING ACCEPT [0:0]
 +
:OUTPUT ACCEPT [0:0]
  
# Forward traffic to ISP
+
# Create a log drop chain
-A FWD_ETH0 -s 192.168.1.0/24 -j ACCEPT
+
:LOG_DROP_BOGON - [0:0]
  
# Forward traffic to VPN
+
# Create an output chain
-A FWD_ETH0 -s 192.168.2.0/24 -j ACCEPT
+
:OUT_PPP0 - [0:0]
 +
:OUT_TUN0 - [0:0]
  
# Prevent 192.168.3.0/24 from accessing internet
+
# Allows traffic from VPN tunnel
-A FWD_ETH0 -s 192.168.3.0/24 -j LOG_REJECT_LANONLY
+
-A PREROUTING -s 172.16.32.0/20 -i tun0 -j ACCEPT
  
# Allow excepted server to be FORWARD to ppp0
+
# Allows traffic to VPN tunnel
#-A FWD_ETH0 -s 192.168.2.0/24 -d <IP_OF_EXCEPTED_SERVER>/32 -o ppp0 -j ACCEPT
+
-A PREROUTING -d 172.16.32.0/20 -j ACCEPT
  
# Forward SSH packets from network to modem
+
# Block specified bogons coming in from ISP and VPN
-A FWD_ETH1 -s 192.168.0.1/32 -d 192.168.1.0/24 -p tcp -m tcp --sport 22 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
+
# (unlikely to happen as they filter them on their router)
-A FWD_ETH1 -s 192.168.0.1/32 -d 192.168.2.0/24 -p tcp -m tcp --sport 22 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
+
-A PREROUTING -i ppp0 -m set --match-set bogon-bn-nonagg src -j LOG_DROP_BOGON
 +
-A PREROUTING -i tun0 -m set --match-set bogon-bn-nonagg src -j LOG_DROP_BOGON
  
# Forward HTTP packets from network to mode
+
# Allows my excepted ranges.
-A FWD_ETH1 -s 192.168.0.1/32 -d 192.168.1.0/24 -p tcp -m tcp --sport 80 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
+
-A PREROUTING -m set --match-set allowed-nets-ipv4 src,src -j ACCEPT
-A FWD_ETH1 -s 192.168.0.1/32 -d 192.168.2.0/24 -p tcp -m tcp --sport 80 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
 
  
# Forward Bittorrent Port to workstation
+
# Pass output interface to corresponding chain
-A FWD_TUN0 -d 192.168.2.20/32 -p tcp -m tcp --dport 6881:6889 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
+
-A OUTPUT -o ppp0 -j OUT_PPP0
-A FWD_TUN0 -d 192.168.2.20/32 -p udp -m udp --dport 6881:6889 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
+
-A OUTPUT -o tun0 -j OUT_TUN0
  
# SSH to Router
+
# Log drop chain
-A IN_ETH0 -s 192.168.1.0/24 -p tcp -m tcp --dport 22 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
+
-A LOG_DROP_BOGON -j LOG --log-prefix "Dropped Bogon (ipv4) : " --log-level 6
-A IN_ETH0 -s 192.168.2.0/24 -p tcp -m tcp --dport 22 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
+
-A LOG_DROP_BOGON -j DROP
  
# DNS to Router
+
# Block packets originating from the router destined to bogon ranges
-A IN_ETH0 -s 192.168.1.0/24 -p udp -m udp --dport 53 -m conntrack --ctstate NEW -j ACCEPT
+
-A OUT_PPP0 -m set --match-set bogon-bn-nonagg dst -j LOG_DROP_BOGON
-A IN_ETH0 -s 192.168.2.0/24 -p udp -m udp --dport 53 -m conntrack --ctstate NEW -j ACCEPT
 
  
# FreeRadius Client (eg a UniFi AP)
+
# Blocks packets originating from the router destined to bogon ranges
-A IN_ETH0 -s 192.168.3.10/32 -p tcp -m tcp --dport 1812 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
+
-A OUT_TUN0 -d 172.16.32.0/20 -j ACCEPT
-A IN_ETH0 -s 192.168.3.10/32 -p udp -m udp --dport 1812 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
+
-A OUT_TUN0 -m set --match-set bogon-bn-nonagg dst -j LOG_DROP_BOGON
 +
COMMIT
  
# Ubiquiti UAP Device Discovery Broadcast
+
#
-A IN_ETH0 -s 192.168.3.10/32 -p udp -m udp --dport 10001 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
+
# NAT Table
 +
# This is where translation of packets happens and "forwarding" of ports
 +
# to specific hosts.
 +
#
 +
*nat
 +
:PREROUTING ACCEPT [0:0]
 +
:INPUT ACCEPT [0:0]
 +
:OUTPUT ACCEPT [0:0]
 +
:POSTROUTING ACCEPT [0:0]
  
# NTP to Router
+
# Port forwarding for Bittorrent
-A IN_ETH0 -s 192.168.1.0/24 -p udp -m udp --dport 123 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
+
-A PREROUTING -i tun0 -p tcp -m tcp --dport 6881:6889 -j DNAT --to-destination 192.168.2.20
-A IN_ETH0 -s 192.168.2.0/24 -p udp -m udp --dport 123 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
+
-A PREROUTING -i tun0 -p udp -m udp --dport 6881:6889 -j DNAT --to-destination 192.168.2.20
-A IN_ETH0 -s 192.168.3.0/24 -p udp -m udp --dport 123 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
 
  
# Accept traffic to router on both subnets
+
# Allows routing to our modem subnet so we can access the web interface
-A IN_ETH0 -s 192.168.1.0/24 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
+
-A POSTROUTING -s 192.168.1.0/24 -d 192.168.0.1/32 -o eth1 -p tcp -m tcp --dport 80 -j MASQUERADE
-A IN_ETH0 -s 192.168.2.0/24 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
+
-A POSTROUTING -s 192.168.2.0/24 -d 192.168.0.1/32 -o eth1 -p tcp -m tcp --dport 80 -j MASQUERADE
  
# Allow excepted server to be INPUT to eth0 from LAN
+
# Allows hosts of the network to use the VPN tunnel
#-A IN_ETH0 -s 192.168.2.0/24 -d <IP_OF_EXCEPTED_SERVER>/32 -o ppp0 -j ACCEPT
+
-A POSTROUTING -o tun0 -j MASQUERADE
  
# SSH To Modem from Router
+
# Allows hosts of the network to use the PPP tunnel
-A IN_ETH1 -s 192.168.0.1/32 -d 192.168.0.0/30 -p tcp -m tcp --sport 22 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
+
-A POSTROUTING -o ppp0 -j MASQUERADE
 +
COMMIT
  
# HTTP To Modem from Router
+
#
-A IN_ETH1 -s 192.168.0.1/32 -d 192.168.0.0/30 -p tcp -m tcp --sport 80 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
+
# Filter Table
 +
# This is where we decide to ACCEPT, DROP or REJECT things
 +
#
 +
*filter
 +
:INPUT DROP [0:0]
 +
:FORWARD DROP [0:0]
 +
:OUTPUT ACCEPT [0:0]
  
# Accept incoming tracked PPP0 connection
+
# Create rule chain per input interface for forwarding packets
-A IN_PPP0 -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT
+
:FWD_ETH0 - [0:0]
 +
:FWD_ETH1 - [0:0]
 +
:FWD_PPP0 - [0:0]
 +
:FWD_TUN0 - [0:0]
  
# Log dropped packets coming in on PPP0
+
# Create rule chain per input interface for input packets (for host itself)
-A IN_PPP0 -j LOG --log-prefix "DROP:INPUT (ipv4) " --log-level 6
+
:IN_ETH0 - [0:0]
-A IN_PPP0 -j LOG_DROP
+
:IN_ETH1 - [0:0]
 +
:IN_PPP0 - [0:0]
 +
:IN_TUN0 - [0:0]
  
# Accept incoming tracked TUN0 connection
+
# Create a drop chain
-A IN_TUN0 -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT
+
:LOG_DROP - [0:0]
  
# Log dropped packets coming in on TUN0
+
# Create a log drop chain
-A IN_TUN0 -j LOG --log-prefix "DROP:INPUT (ipv4) " --log-level 6
+
:LOG_DROP_BOGON - [0:0]
-A IN_TUN0 -j LOG_DROP
 
  
# Log dropped bogons that never got forwarded
+
# Create a reject chain
-A LOG_DROP_BOGON -j LOG --log-prefix "Dropped Bogon forward (ipv4) " --log-level 6
+
:LOG_REJECT_LANONLY - [0:0]
-A LOG_DROP_BOGON -j DROP
 
  
# Log rejected packets
+
# Create an output chain
-A LOG_REJECT_LANONLY -j LOG --log-prefix "Rejected packet from LAN only range : " --log-level 6
+
:OUT_PPP0 - [0:0]
-A LOG_REJECT_LANONLY -j REJECT --reject-with icmp-port-unreachable
+
:OUT_TUN0 - [0:0]
COMMIT
 
  
#
+
# Pass input packet to corresponding rule chain
# Mangle Table
+
-A INPUT -i lo -j ACCEPT
# This is the place where our markings happen, whether they be 0x1 or 0x2
+
-A INPUT -i eth0 -j IN_ETH0
#
+
-A INPUT -i eth1 -j IN_ETH1
*mangle
+
-A INPUT -i ppp0 -j IN_PPP0
 +
-A INPUT -i tun0 -j IN_TUN0
  
# Set default policies for table
+
# Track forwarded packets
:PREROUTING ACCEPT [0:0]
+
-A FORWARD -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT
:INPUT ACCEPT [0:0]
 
:FORWARD ACCEPT [0:0]
 
:OUTPUT ACCEPT [0:0]
 
:POSTROUTING ACCEPT [0:0]
 
  
# Restore CONNMARK to the MARK (If one doesn't exist then no mark is set)
+
# Pass forwarded packet to corresponding rule chain
-A PREROUTING -j CONNMARK --restore-mark --nfmask 0xffffffff --ctmask 0xffffffff
+
-A FORWARD -i eth0 -j FWD_ETH0
 +
-A FORWARD -i eth1 -j FWD_ETH1
 +
-A FORWARD -i ppp0 -j FWD_PPP0
 +
-A FORWARD -i tun0 -j FWD_TUN0
  
# If packet MARK is 2, then it means there is already a connection mark and the
+
# Pass output interface to corresponding chain
# original packet came in on VPN
+
-A OUTPUT -o ppp0 -j OUT_PPP0
-A PREROUTING -s 192.168.2.0/24 -m mark --mark 0x2 -j ACCEPT
+
-A OUTPUT -o tun0 -j OUT_TUN0
  
# Check exception (this is a server which when accessed on a 192.168.2.0/24 address will go out the ISP table) are 0x1
+
# Forward traffic to Modem
#-A PREROUTING -s 192.168.2.0/24 -d <IP_OF_EXCEPTED_SERVER>/32 -m mark --mark 0x1 -j ACCEPT
+
-A FWD_ETH0 -d 192.168.0.1/32 -j ACCEPT
  
# Mark packets coming from 192.168.2.0/24 are 0x2
+
# Allow routing to remote address on VPN
-A PREROUTING -s 192.168.2.0/24 -j MARK --set-xmark 0x2/0xffffffff
+
-A FWD_ETH0 -s 192.168.1.0/24 -d 172.16.32.1/32 -o tun0 -j ACCEPT
 +
-A FWD_ETH0 -s 192.168.2.0/24 -d 172.16.32.1/32 -o tun0 -j ACCEPT
  
# If packet MARK is 1, then it means there is already a connection mark and the
+
# Allow forwarding from LAN hosts to LAN ONLY subnet
# original packet came in on ISP
+
-A FWD_ETH0 -s 192.168.1.0/24 -d 192.168.3.0/24 -j ACCEPT
-A PREROUTING -s 192.168.1.0/24 -m mark --mark 0x1 -j ACCEPT
+
-A FWD_ETH0 -s 192.168.2.0/24 -d 192.168.3.0/24 -j ACCEPT
  
# Mark packets 192.168.1.0/24 are 0x1
+
# Allow LAN ONLY subnet to contact other LAN hosts
-A PREROUTING -s 192.168.1.0/24 -j MARK --set-xmark 0x1/0xffffffff
+
-A FWD_ETH0 -s 192.168.3.0/24 -d 192.168.1.0/24 -j ACCEPT
 +
-A FWD_ETH0 -s 192.168.3.0/24 -d 192.168.2.0/24 -j ACCEPT
  
# Mark exception (this is a server which when accessed on a 192.168.2.0/24 address will go out the ISP table) as 0x1
+
# Refuse to forward bogons to the internet!
#-A PREROUTING -s 192.168.2.0/24 -d <IP_OF_EXCEPTED_SERVER>/32 -j MARK --set-xmark 0x1/0xffffff
+
-A FWD_ETH0 -m set --match-set bogon-bn-nonagg dst -j LOG_DROP_BOGON
  
# Strip mark if packet is destined for modem
+
# Forward traffic to ISP
-A PREROUTING -d 192.168.0.1/32 -j MARK --set-xmark 0x0/0xffffffff
+
-A FWD_ETH0 -s 192.168.1.0/24 -j ACCEPT
  
# Save MARK to CONNMARK (remember iproute can't see CONNMARKs)
+
# Forward traffic to VPN
-A PREROUTING -j CONNMARK --save-mark --nfmask 0xffffffff --ctmask 0xffffffff
+
-A FWD_ETH0 -s 192.168.2.0/24 -j ACCEPT
COMMIT</pre>
 
  
= Other Tips =
+
# Prevent 192.168.3.0/24 from accessing internet
 +
-A FWD_ETH0 -s 192.168.3.0/24 -j LOG_REJECT_LANONLY
  
== Diagnosing firewall problems ==
+
# Allow excepted server to be FORWARD to ppp0
 +
#-A FWD_ETH0 -s 192.168.2.0/24 -d <IP_OF_EXCEPTED_SERVER>/32 -o ppp0 -j ACCEPT
  
=== netcat, netcat6 ===
+
# Forward SSH packets from network to modem
Netcat can be useful for testing if a port is open or closed or filtered.
+
-A FWD_ETH1 -s 192.168.0.1/32 -d 192.168.1.0/24 -p tcp -m tcp --sport 22 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
 +
-A FWD_ETH1 -s 192.168.0.1/32 -d 192.168.2.0/24 -p tcp -m tcp --sport 22 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
  
{{cmd|apk add netcat-openbsd}}
+
# Forward HTTP packets from network to mode
 +
-A FWD_ETH1 -s 192.168.0.1/32 -d 192.168.1.0/24 -p tcp -m tcp --sport 80 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
 +
-A FWD_ETH1 -s 192.168.0.1/32 -d 192.168.2.0/24 -p tcp -m tcp --sport 80 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
  
After installing netcat we can use it like this:
+
# Forward Bittorrent Port to workstation
 +
-A FWD_TUN0 -d 192.168.2.20/32 -p tcp -m tcp --dport 6881:6889 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
 +
-A FWD_TUN0 -d 192.168.2.20/32 -p udp -m udp --dport 6881:6889 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
  
Say we wanted to test for IPv6, UDP, Port 547 we would do this on the router:
+
# SSH to Router
 +
-A IN_ETH0 -s 192.168.1.0/24 -p tcp -m tcp --dport 22 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
 +
-A IN_ETH0 -s 192.168.2.0/24 -p tcp -m tcp --dport 22 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
  
{{cmd|nc -6 -u -l 547}}
+
# DNS to Router
 +
-A IN_ETH0 -s 192.168.1.0/24 -p udp -m udp --dport 53 -m conntrack --ctstate NEW -j ACCEPT
 +
-A IN_ETH0 -s 192.168.2.0/24 -p udp -m udp --dport 53 -m conntrack --ctstate NEW -j ACCEPT
  
and then this on the client to connect to it:
+
# FreeRadius Client (eg a UniFi AP)
 +
-A IN_ETH0 -s 192.168.3.10/32 -p tcp -m tcp --dport 1812 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
 +
-A IN_ETH0 -s 192.168.3.10/32 -p udp -m udp --dport 1812 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
  
{{cmd|nc -u -v -6 2001:0db8:1234:0001::1 547}}
+
# Ubiquiti UAP Device Discovery Broadcast
 +
-A IN_ETH0 -s 192.168.3.10/32 -p udp -m udp --dport 10001 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
  
=== tcpdump ===
+
# NTP to Router
 +
-A IN_ETH0 -s 192.168.1.0/24 -p udp -m udp --dport 123 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
 +
-A IN_ETH0 -s 192.168.2.0/24 -p udp -m udp --dport 123 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
 +
-A IN_ETH0 -s 192.168.3.0/24 -p udp -m udp --dport 123 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
  
tcpdump can also be useful for dumping the contents of packets coming in on an interface:
+
# Accept traffic to router on both subnets
 +
-A IN_ETH0 -s 192.168.1.0/24 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
 +
-A IN_ETH0 -s 192.168.2.0/24 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
  
{{cmd|apk add tcpdump}}
+
# Allow excepted server to be INPUT to eth0 from LAN
 +
#-A IN_ETH0 -s 192.168.2.0/24 -d <IP_OF_EXCEPTED_SERVER>/32 -o ppp0 -j ACCEPT
  
Then we can run it. This example captures all DNS traffic originating from 192.168.2.20.
+
# SSH To Modem from Router
 +
-A IN_ETH1 -s 192.168.0.1/32 -d 192.168.0.0/30 -p tcp -m tcp --sport 22 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
  
{{cmd|tcpdump -i eth0 udp and src 192.168.2.20 and port 53}}
+
# HTTP To Modem from Router
 +
-A IN_ETH1 -s 192.168.0.1/32 -d 192.168.0.0/30 -p tcp -m tcp --sport 80 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
  
You can write the file out with the -w option, and view it in Wireshark locally on your computer. You can increase the verbosity with the -v option. Using -vv will be even more verbose. -vvv will show even more.
+
# Accept incoming tracked PPP0 connection
 +
-A IN_PPP0 -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT
  
== lbu cache ==
+
# Log dropped packets coming in on PPP0
Configure lbu cache so that you don't need to download packages when you restart your router eg [[Local APK cache]]
+
-A IN_PPP0 -j LOG --log-prefix "DROP:INPUT (ipv4) " --log-level 6
 +
-A IN_PPP0 -j LOG_DROP
  
This is particularly important as some of the images do not contain ppp-pppoe. This might mean you're unable to get an internet connection to download the other packages on boot.
+
# Accept incoming tracked TUN0 connection
 +
-A IN_TUN0 -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT
  
== lbu encryption /etc/lbu/lbu.conf ==
+
# Log dropped packets coming in on TUN0
In /etc/lbu/lbu.conf you might want to enable encryption to protect your VPN keys.
+
-A IN_TUN0 -j LOG --log-prefix "DROP:INPUT (ipv4) " --log-level 6
 +
-A IN_TUN0 -j LOG_DROP
  
<pre># what cipher to use with -e option
+
# Log dropped bogons that never got forwarded
DEFAULT_CIPHER=aes-256-cbc
+
-A LOG_DROP_BOGON -j LOG --log-prefix "Dropped Bogon forward (ipv4) " --log-level 6
 +
-A LOG_DROP_BOGON -j DROP
  
# Uncomment the row below to encrypt config by default
+
# Log rejected packets
ENCRYPTION=$DEFAULT_CIPHER
+
-A LOG_REJECT_LANONLY -j LOG --log-prefix "Rejected packet from LAN only range : " --log-level 6
 +
-A LOG_REJECT_LANONLY -j REJECT --reject-with icmp-port-unreachable
 +
COMMIT
  
# Uncomment below to avoid <media> option to 'lbu commit'
+
#
# Can also be set to 'floppy'
+
# Mangle Table
LBU_MEDIA=mmcblk0p1
+
# This is the place where our markings happen, whether they be 0x1 or 0x2
 +
#
 +
*mangle
  
# Set the LBU_BACKUPDIR variable in case you prefer to save the apkovls
+
# Set default policies for table
# in a normal directory instead of mounting an external media.
+
:PREROUTING ACCEPT [0:0]
# LBU_BACKUPDIR=/root/config-backups
+
:INPUT ACCEPT [0:0]
 +
:FORWARD ACCEPT [0:0]
 +
:OUTPUT ACCEPT [0:0]
 +
:POSTROUTING ACCEPT [0:0]
  
# Uncomment below to let lbu make up to 3 backups
+
# Restore CONNMARK to the MARK (If one doesn't exist then no mark is set)
# BACKUP_LIMIT=3</pre>
+
-A PREROUTING -j CONNMARK --restore-mark --nfmask 0xffffffff --ctmask 0xffffffff
  
Remember to set a root password, by default Alpine Linux's root account is passwordless.
+
# If packet MARK is 2, then it means there is already a connection mark and the
{{cmd|passwd root}}
+
# original packet came in on VPN
 +
-A PREROUTING -s 192.168.2.0/24 -m mark --mark 0x2 -j ACCEPT
  
== Backup apkprov ==
+
# Check exception (this is a server which when accessed on a 192.168.2.0/24 address will go out the ISP table) are 0x1
It's a good idea to back up your apk provision file. You can pull it off your router to your local workstation with:
+
#-A PREROUTING -s 192.168.2.0/24 -d <IP_OF_EXCEPTED_SERVER>/32 -m mark --mark 0x1 -j ACCEPT
  
{{cmd|scp -r root@192.168.2.1:/media/mmcblk0p1/<YOUR HOST NAME>.apkovl.tar.gz.aes-256-cbc ./}}
+
# Mark packets coming from 192.168.2.0/24 are 0x2
 +
-A PREROUTING -s 192.168.2.0/24 -j MARK --set-xmark 0x2/0xffffffff
  
And decrypt it with:
+
# If packet MARK is 1, then it means there is already a connection mark and the
{{cmd|openssl enc -d -aes-256-cbc -in <YOUR HOST NAME>.apkovl.tar.gz.aes-256-cbc -out <YOUR HOST NAME>.apkovl.tar.gz}}
+
# original packet came in on ISP
 +
-A PREROUTING -s 192.168.1.0/24 -m mark --mark 0x1 -j ACCEPT
 +
 
 +
# Mark packets 192.168.1.0/24 are 0x1
 +
-A PREROUTING -s 192.168.1.0/24 -j MARK --set-xmark 0x1/0xffffffff
  
It can be encrypted with:
+
# Mark exception (this is a server which when accessed on a 192.168.2.0/24 address will go out the ISP table) as 0x1
{{cmd|openssl aes-256-cbc -salt -in <YOUR HOST NAME>.apkovl.tar.gz -out <YOUR HOST NAME>.apkovl.tar.gz.aes-256-cbc}}
+
#-A PREROUTING -s 192.168.2.0/24 -d <IP_OF_EXCEPTED_SERVER>/32 -j MARK --set-xmark 0x1/0xffffff
  
== Harden SSH ==
+
# Strip mark if packet is destined for modem
 +
-A PREROUTING -d 192.168.0.1/32 -j MARK --set-xmark 0x0/0xffffffff
  
=== Generate a SSH key ===
+
# Save MARK to CONNMARK (remember iproute can't see CONNMARKs)
{{cmd|ssh-keygen -t rsa -b 4096}}
+
-A PREROUTING -j CONNMARK --save-mark --nfmask 0xffffffff --ctmask 0xffffffff
 +
COMMIT</pre>
  
You will want to put the contents of id_rsa.pub in /etc/ssh/authorized_keys
+
= Other Tips =
  
You can put multiple public keys on multiple lines if more than one person has access to the router.
+
== Diagnosing firewall problems ==
  
=== /etc/ssh/sshd_config ===
+
=== netcat, netcat6 ===
A couple of good options to set in here can be:
+
Netcat can be useful for testing if a port is open or closed or filtered.
 +
 
 +
{{cmd|apk add netcat-openbsd}}
 +
 
 +
After installing netcat we can use it like this:
 +
 
 +
Say we wanted to test for IPv6, UDP, Port 547 we would do this on the router:
 +
 
 +
{{cmd|nc -6 -u -l 547}}
 +
 
 +
and then this on the client to connect to it:
 +
 
 +
{{cmd|nc -u -v -6 2001:0db8:1234:0001::1 547}}
 +
 
 +
=== tcpdump ===
 +
 
 +
tcpdump can also be useful for dumping the contents of packets coming in on an interface:
 +
 
 +
{{cmd|apk add tcpdump}}
 +
 
 +
Then we can run it. This example captures all DNS traffic originating from 192.168.2.20.
 +
 
 +
{{cmd|tcpdump -i eth0 udp and src 192.168.2.20 and port 53}}
 +
 
 +
You can write the file out with the -w option, and view it in Wireshark locally on your computer. You can increase the verbosity with the -v option. Using -vv will be even more verbose. -vvv will show even more.
 +
 
 +
== lbu cache ==
 +
Configure lbu cache so that you don't need to download packages when you restart your router eg [[Local APK cache]]
 +
 
 +
This is particularly important as some of the images do not contain ppp-pppoe. This might mean you're unable to get an internet connection to download the other packages on boot.
 +
 
 +
== lbu encryption /etc/lbu/lbu.conf ==
 +
In /etc/lbu/lbu.conf you might want to enable encryption to protect your VPN keys.
 +
 
 +
<pre># what cipher to use with -e option
 +
DEFAULT_CIPHER=aes-256-cbc
 +
 
 +
# Uncomment the row below to encrypt config by default
 +
ENCRYPTION=$DEFAULT_CIPHER
 +
 
 +
# Uncomment below to avoid <media> option to 'lbu commit'
 +
# Can also be set to 'floppy'
 +
LBU_MEDIA=mmcblk0p1
 +
 
 +
# Set the LBU_BACKUPDIR variable in case you prefer to save the apkovls
 +
# in a normal directory instead of mounting an external media.
 +
# LBU_BACKUPDIR=/root/config-backups
 +
 
 +
# Uncomment below to let lbu make up to 3 backups
 +
# BACKUP_LIMIT=3</pre>
 +
 
 +
Remember to set a root password, by default Alpine Linux's root account is passwordless.
 +
{{cmd|passwd root}}
 +
 
 +
== Backup apkprov ==
 +
It's a good idea to back up your apk provision file. You can pull it off your router to your local workstation with:
 +
 
 +
{{cmd|scp -r root@192.168.2.1:/media/mmcblk0p1/<YOUR HOST NAME>.apkovl.tar.gz.aes-256-cbc ./}}
 +
 
 +
And decrypt it with:
 +
{{cmd|openssl enc -d -aes-256-cbc -in <YOUR HOST NAME>.apkovl.tar.gz.aes-256-cbc -out <YOUR HOST NAME>.apkovl.tar.gz}}
 +
 
 +
It can be encrypted with:
 +
{{cmd|openssl aes-256-cbc -salt -in <YOUR HOST NAME>.apkovl.tar.gz -out <YOUR HOST NAME>.apkovl.tar.gz.aes-256-cbc}}
 +
 
 +
== Harden SSH ==
 +
 
 +
=== Generate a SSH key ===
 +
{{cmd|ssh-keygen -t rsa -b 4096}}
 +
 
 +
You will want to put the contents of id_rsa.pub in /etc/ssh/authorized_keys
 +
 
 +
You can put multiple public keys on multiple lines if more than one person has access to the router.
 +
 
 +
=== /etc/ssh/sshd_config ===
 +
A couple of good options to set in here can be:
  
 
<pre>ListenAddress 192.168.1.1
 
<pre>ListenAddress 192.168.1.1
ListenAddress 192.168.2.1</pre>
+
ListenAddress 192.168.2.1</pre>
 
+
 
While this isn't usually a good idea, a router doesn't need more than one user.
+
While this isn't usually a good idea, a router doesn't need more than one user.
<pre>PermitRootLogin yes</pre>
+
<pre>PermitRootLogin yes</pre>
 +
 
 +
The most important options:
 +
<pre>RSAAuthentication yes
 +
PubkeyAuthentication yes
 +
AuthorizedKeysFile  /etc/ssh/authorized_keys
 +
PasswordAuthentication no
 +
PermitEmptyPasswords no
 +
AllowTcpForwarding no
 +
X11Forwarding no</pre>
 +
 
 +
=== /etc/conf.d/sshd ===
 +
You will want to add <pre>rc_need="net"</pre>
 +
 
 +
This instructs OpenRC to make sure the network is up before starting ssh.
 +
 
 +
Finally add sshd to the default run level
 +
{{cmd|rc-update add sshd default}}
 +
 
 +
 
 +
Additionally you may want to look at [https://stribika.github.io/2015/01/04/secure-secure-shell.html Secure Secure Shell] and tighten OpenSSH's cryptography options.
 +
 
 +
= References =
 +
* https://wiki.gentoo.org/wiki/Home_Router
 +
* https://help.ubuntu.com/community/ADSLPPPoE
 +
* https://wiki.archlinux.org/index.php/Router
 +
* https://wiki.gentoo.org/wiki/IPv6_router_guide
 +
* [https://vk5tu.livejournal.com/37206.html IPv6 at home, under the hood with Debian Wheezy and Internode]
 +
* [http://vk5tu.livejournal.com/43059.html Raspberry Pi random number generator]
 +
* [https://www.raspberrypi.org/forums/viewtopic.php?f=56&t=60569 rng-tools post by ktb]
  
The most important options:
+
[[category: VPN]]
<pre>RSAAuthentication yes
+
[[category: Raspberry]]
PubkeyAuthentication yes
 
AuthorizedKeysFile  /etc/ssh/authorized_keys
 
PasswordAuthentication no
 
PermitEmptyPasswords no
 
AllowTcpForwarding no
 
X11Forwarding no</pre>
 
 
 
=== /etc/conf.d/sshd ===
 
You will want to add <pre>rc_need="net"</pre>
 
 
 
This instructs OpenRC to make sure the network is up before starting ssh.
 
 
 
Finally add sshd to the default run level
 
{{cmd|rc-update add sshd default}}
 
 
 
= References =
 
* https://wiki.gentoo.org/wiki/Home_Router
 
* https://help.ubuntu.com/community/ADSLPPPoE
 
* https://wiki.archlinux.org/index.php/Router
 
* https://wiki.gentoo.org/wiki/IPv6_router_guide
 
* [https://vk5tu.livejournal.com/37206.html IPv6 at home, under the hood with Debian Wheezy and Internode]
 
* [http://vk5tu.livejournal.com/43059.html Raspberry Pi random number generator]
 
* [https://www.raspberrypi.org/forums/viewtopic.php?f=56&t=60569 rng-tools post by ktb]
 

Latest revision as of 10:03, 25 February 2020

Contents

Rationale

This guide demonstrates how to set up a Linux router with a VPN tunnel. You will need a second ethernet adapter. If you are using a Raspberry Pi like I did, then you can use something like this Apple USB Ethernet Adapter as it contains a ASIX AX88772 which has good Linux support.

You may choose to also buy an RTC clock. If you don't have an RTC clock, the time is lost when your Pi is shut down. When it is rebooted, the time will be set back to Thursday, 1 January 1970. As this is earlier than the creation time of your VPN certificates OpenVPN will refuse to start, which may mean you cannot do DNS lookups over VPN.

For wireless, a separate access point was purchased (Ubiquiti UniFi AP) because it contains a Atheros AR9287 which is supported by ath9k.

I only chose a Raspberry Pi due to the fact it was inexpensive. My WAN link is pathetic so I was not concerned with getting high PPS (Packets Per Second). You could choose to use an old x86/amd64 system instead. If I had better internet I'd probably go with an offering from Soekris such as the net6501 as it would have a much lower power consumption than a generic x86_64 desktop processor.

If you want to route speeds above 100 Mbit/s you'll want to make use of hardware encryption like AES-NI. The Soekris offerings have the option of an additional hardware encryption module (vpn1411). Another option is to use a Mini ITX motherboard, with a managed switch. I chose the Ubiquiti ES-16-150W.

If you wish to use IPv6 you should consider looking at Linux Router with VPN on a Raspberry Pi (IPv6) as the implementation does differ slightly to this tutorial.

The network in this tutorial looks like this:

Network Diagram Single IPv4

Installation

This guide assumes you're using Alpine Linux from a micro SD card in ramdisk mode. It assumes you've read the basics of how to use Alpine local backup. The Raspberry Pi article contains information on how to install Alpine Linux on a Raspberry Pi.

Modem in full bridge mode

This particular page uses an example where you have a modem that uses PPPoE. You will need to modify parts which do not apply to you.

In this example I have a modem which has been configured in full bridge mode. PPP sessions are initiated on the router.

The modem I am using is a Cisco 877 Integrated Services Router. It has no web interface and is controlled over SSH. More information can be found Configuring a Cisco 877 in full bridge mode.

Network

/etc/hostname

Set this to your hostname eg:

<HOST_NAME>

/etc/hosts

Set your host and hostname

127.0.0.1	<HOST_NAME> <HOST_NAME>.<DOMAIN_NAME>

::1		<HOST_NAME> ipv6-gateway ipv6-loopback
ff00::0		ipv6-localnet
ff00::0		ipv6-mcastprefix
ff02::1		ipv6-allnodes
ff02::2		ipv6-allrouters
ff02::3		ipv6-allhosts

/etc/network/interfaces

Configure your network interfaces. Change "yourISP" to the file name of the file in /etc/ppp/peers/yourISP

#
# Network Interfaces
#

# Loopback interfaces
auto lo
iface lo inet loopback
  address 127.0.0.1
  netmask 255.0.0.0

# Internal Interface - facing LAN
auto eth0
iface eth0 inet static
  address 192.168.1.1
  netmask 255.255.255.0
  broadcast 192.168.1.255


PPP

Next up we need to configure our router to be able to dial a PPP connection with our modem.

If your ISP uses PPP you may need to configure it. See PPP.

You will want to make sure you set your WAN interface, in this example we used eth1.

# External Interface - facing Modem
allow-hotplug eth1
auto eth1
iface eth1 inet static
  address 192.168.0.2
  netmask 255.255.255.252
  broadcast 192.168.0.3
  pre-up /sbin/ip link set eth1 up
  up ifup ppp0=yourISP
  down ifdown ppp0=yourISP
  post-down /sbin/ip link set eth1 up

# Link to ISP
iface yourISP inet ppp
  provider yourISP

IPoE

Alternatively it's quite common for ISPs to use IPoE. IPoE is much simpler and only runs DHCP on the external interface. It should look something like:

# External interface to ISP
allow-hotplug eth1
auto eth1
iface eth1 inet dhcp

iface eth1 inet static
    address 192.168.0.2
    netmask 255.255.255.252
    broadcast 192.168.0.3

iface eth1 inet6 manual

DHCP from ISP

Above we set DHCP and we set a static IP. The purpose of this is so we can still forward packets through to the modem to be able to access the web interface or ssh.

We do still need DHCP to get an IP address form our ISP though. I like to use dhcpcd instead of udhcp (the default in Alpine Linux), because it allows for Prefix Delegation, which is used in IPv6 networks.

My /etc/dhcpcd.conf looks like this:

# Enable extra debugging
# debug
# logfile /var/log/dhcpcd.log

# Allow users of this group to interact with dhcpcd via the control
# socket.
#controlgroup wheel

# Inform the DHCP server of our hostname for DDNS.
hostname gateway

# Use the hardware address of the interface for the Client ID.
# clientid
# or
# Use the same DUID + IAID as set in DHCPv6 for DHCPv4 ClientID as
# per RFC4361. Some non-RFC compliant DHCP servers do not reply with
# this set. In this case, comment out duid and enable clientid above.
duid

# Persist interface configuration when dhcpcd exits.
persistent

# Rapid commit support.
# Safe to enable by default because it requires the equivalent option
# set on the server to actually work.
option rapid_commit

# A list of options to request from the DHCP server.
option domain_name_servers, domain_name, domain_search, host_name
option classless_static_routes

# Most distributions have NTP support.
option ntp_servers

# Respect the network MTU.
# Some interface drivers reset when changing the MTU so disabled by
# default.
#option interface_mtu 1586

# A ServerID is required by RFC2131.
require dhcp_server_identifier

# Generate Stable Private IPv6 Addresses instead of hardware based
# ones
slaac private

# A hook script is provided to lookup the hostname if not set by the
# DHCP server, but it should not be run by default.
nohook lookup-hostname

# Disable solicitations on all interfaces
noipv6rs

# Wait for IP before forking to background
waitip 6

# Don't touch DNS
nohook resolv.conf

allowinterfaces eth1 eth0.2
# Use the interface connected to WAN
interface eth1
    waitip 4
    noipv4ll
    ipv6rs # enable routing solicitation get the default IPv6 route
    iaid 1
    ia_pd 1/::/56 eth0.2/2/64
    timeout 30

interface eth0.2
    ipv6only

Basic IPtables firewall with routing

This demonstrates how to set up basic routing with a permissive outgoing firewall. Incoming packets are blocked. The rest is commented in the rule set.

First install iptables:

apk add iptables ip6tables

#########################################################################
# Basic iptables IPv4 routing rule set
#
# 192.168.1.0/24 routed directly to PPP0 via NAT
# 
#########################################################################

#
# Mangle Table
# We leave this empty for the moment.
#
*mangle
:PREROUTING ACCEPT [0:0]
:INPUT ACCEPT [0:0]
:FORWARD ACCEPT [0:0]
:OUTPUT ACCEPT [0:0]
:POSTROUTING ACCEPT [0:0]
COMMIT

#
# Filter Table
# This is where we decide to ACCEPT, DROP or REJECT things
#
*filter
:INPUT DROP [0:0]
:FORWARD DROP [0:0]
:OUTPUT ACCEPT [0:0]
*filter

# Create rule chain per input interface for forwarding packets
:FWD_ETH0 - [0:0]
:FWD_ETH1 - [0:0]
:FWD_PPP0 - [0:0]

# Create rule chain per input interface for input packets (for host itself)
:IN_ETH0 - [0:0]
:IN_ETH1 - [0:0]
:IN_PPP0 - [0:0]

# Create a log drop chain
:LOG_DROP - [0:0]

# Pass input packet to corresponding rule chain
-A INPUT -i lo -j ACCEPT
-A INPUT -i eth0 -j IN_ETH0
-A INPUT -i eth1 -j IN_ETH1
-A INPUT -i ppp0 -j IN_PPP0

# Pass forwarded packet to corresponding rule chain
-A FORWARD -i eth0 -j FWD_ETH0
-A FORWARD -i eth1 -j FWD_ETH1
-A FORWARD -i ppp0 -j FWD_PPP0

# Forward LAN traffic out
-A FWD_ETH0 -s 192.168.1.0/24 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT

# Forward SSH packets from network to modem
-A FWD_ETH1 -s 192.168.0.0/30 -d 192.168.1.0/24 -p tcp -m tcp --sport 22 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT

# Forward HTTP to modem's webserver
-A FWD_ETH1 -s 192.168.0.0/30 -d 192.168.1.0/24 -p tcp -m tcp --sport 80 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT

# Forward traffic to ISP
-A FWD_PPP0 -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT

# SSH to Router
-A IN_ETH0 -s 192.168.1.0/24 -p tcp -m tcp --dport 22 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT

# DNS to Router
-A IN_ETH0 -s 192.168.1.0/24 -p tcp -m tcp --dport 1812 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT

# FreeRadius Client (eg a UniFi AP)
-A IN_ETH0 -s 192.168.1.0/24 -p udp -m udp --dport 1812 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT

# NTP to Router
-A IN_ETH0 -s 192.168.1.0/24 -p udp -m udp --dport 123 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT

# Accept traffic
-A IN_ETH0 -s 192.168.1.0/24 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT

# SSH To Modem from Router
-A IN_ETH1 -s 192.168.0.1/32 -d 192.168.0.0/30 -p tcp -m tcp --sport 22 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT

# HTTP to modem
-A IN_ETH1 -s 192.168.0.1/32 -d 192.168.0.0/30 -p tcp -m tcp --sport 80 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT

# Accept incoming tracked PPP0 connection
-A IN_PPP0 -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT
COMMIT

#
# NAT Table
# This is where translation of packets happens and "forwarding" of ports
# to specific hosts.
#
*nat
:PREROUTING ACCEPT [0:0]
:INPUT ACCEPT [0:0]
:OUTPUT ACCEPT [0:0]
:POSTROUTING ACCEPT [0:0]

# Port forwarding for Bittorrent
-A PREROUTING -i ppp0 -p tcp -m tcp --dport 6881:6889 -j DNAT --to-destination 192.168.1.20
-A PREROUTING -i ppp0 -p udp -m udp --dport 6881:6889 -j DNAT --to-destination 192.168.1.20

# Allows routing to our modem subnet so we can access the web interface or SSH
-A POSTROUTING -s 192.168.1.0/24 -d 192.168.0.1/32 -o eth1 -p tcp -m tcp --dport 22 -j MASQUERADE
-A POSTROUTING -s 192.168.1.0/24 -d 192.168.0.1/32 -o eth1 -p tcp -m tcp --dport 80 -j MASQUERADE

# Allows hosts of the network to use the PPP tunnel
-A POSTROUTING -s 192.168.1.0/24 -o ppp0 -j MASQUERADE
COMMIT

I'd also highly suggest reading these resources if you are new to iptables:

/etc/sysctl.d/local.conf

# Controls IP packet forwarding
net.ipv4.ip_forward = 1

# Needed to use fwmark, only required if you want to set up the VPN subnet later in this article
net.ipv4.conf.all.rp_filter = 2

# Disable IPv6
net.ipv6.conf.all.disable_ipv6 = 1
net.ipv6.conf.lo.disable_ipv6 = 1
net.ipv6.conf.default.disable_ipv6 = 1

Note IPv6 is disabled here if you want that see the other tutorial Linux Router with VPN on a Raspberry Pi (IPv6). You may also wish to look at ip-sysctl.txt to read about the other keys.

DHCP

apk add dhcp

/etc/conf.d/dhcpd

Specify the configuration file location, interface to run on and that you want DHCPD to run in IPv4 mode.

# /etc/conf.d/dhcpd: config file for /etc/init.d/dhcpd

# If you require more than one instance of dhcpd you can create symbolic
# links to dhcpd service like so
#   cd /etc/init.d
#   ln -s dhcpd dhcpd.foo
#   cd ../conf.d
#   cp dhcpd dhcpd.foo
# Now you can edit dhcpd.foo and specify a different configuration file.
# You'll also need to specify a pidfile in that dhcpd.conf file.
# See the pid-file-name option in the dhcpd.conf man page for details.

# If you wish to run dhcpd in a chroot, uncomment the following line
# DHCPD_CHROOT="/var/lib/dhcp/chroot"

# All file paths below are relative to the chroot.
# You can specify a different chroot directory but MAKE SURE it's empty.

# Specify a configuration file - the default is /etc/dhcp/dhcpd.conf
DHCPD_CONF="/etc/dhcp/dhcpd.conf"

# Configure which interface or interfaces to for dhcpd to listen on.
# List all interfaces space separated. If this is not specified then
# we listen on all interfaces.
DHCPD_IFACE="eth0"

# Insert any other dhcpd options - see the man page for a full list.
DHCPD_OPTS="-4"

/etc/dhcp/dhcpd.conf

Configure your DHCP configuration server. For my DHCP server I'm going to have three subnets. Each has a specific purpose. You may choose to have any number of subnets like below. The broadcast-address would be different if you used VLANs. However in this case we are not.

authoritative;
ddns-update-style interim;

shared-network home {
  subnet 192.168.1.0 netmask 255.255.255.0 {
    range 192.168.1.10 192.168.1.240;
    option subnet-mask 255.255.255.0;
    option broadcast-address 192.168.1.255;
    option routers 192.168.1.1;
    option ntp-servers 192.168.1.1;
    option domain-name-servers 192.168.1.1;
    allow unknown-clients;
  }

  subnet 192.168.2.0 netmask 255.255.255.0 {
    range 192.168.2.10 192.168.2.240;
    option subnet-mask 255.255.255.0;
    option broadcast-address 192.168.2.255;
    option routers 192.168.2.1;
    option ntp-servers 192.168.2.1;
    option domain-name-servers 192.168.1.1;
    ignore unknown-clients;
  }

  subnet 192.168.3.0 netmask 255.255.255.0 {
    range 192.168.3.10 192.168.3.240;
    option subnet-mask 255.255.255.0;
    option broadcast-address 192.168.3.255;
    option routers 192.168.3.1;
    option ntp-servers 192.168.3.1;
    option domain-name-servers 192.168.1.1;
    ignore unknown-clients;
  }
}

host Gaming_Computer {
  hardware ethernet 00:53:00:FF:FF:11;
  fixed-address 192.168.1.20;
  option subnet-mask 255.255.255.0;
  option broadcast-address 192.168.1.255;
  option routers 192.168.1.1;
  option host-name "gaming_computer";
}

host Linux_Workstation {
  hardware ethernet 00:53:00:FF:FF:22;
  fixed-address 192.168.2.21;
  option subnet-mask 255.255.255.0;
  option broadcast-address 192.168.2.255;
  option routers 192.168.2.1;
  option host-name "linux_workstation";
}

host printer {
  hardware ethernet 00:53:00:FF:FF:33;
  fixed-address 192.168.3.9;
  option subnet-mask 255.255.255.0;
  option broadcast-address 192.168.3.255;
  option routers 192.168.3.1;
}

Make sure to add this to the default run level once configured:

rc-update add dhcpd default

Synchronizing the clock

You can choose to use BusyBox's ntpd or you can choose a more fully fledged option like OpenNTPD or Chrony

Busybox /etc/conf.d/ntpd

Allow clients to synchronize their clocks with the router.

# By default ntpd runs as a client. Add -l to run as a server on port 123.
NTPD_OPTS="-l -N -p <REMOTE TIME SERVER>"

Make sure to add this to the default run level once configured:

rc-update add ntpd default

Or if you prefer to synchronize with multiple servers...

Chrony /etc/chrony.conf

apk add chrony

logdir /var/log/chrony
log measurements statistics tracking

allow 192.168.0.0/30
allow 192.168.1.0/24
allow 192.168.2.0/24
allow 192.168.3.0/24
allow 192.168.4.0/24
broadcast 30 192.168.0.3
broadcast 30 192.168.1.255
broadcast 30 192.168.2.255
broadcast 30 192.168.3.255
broadcast 30 192.168.4.255

server 0.pool.ntp.org iburst
server 1.pool.ntp.org iburst
server 2.pool.ntp.org iburst
server 3.pool.ntp.org iburst

initstepslew 10 pool.ntp.org
driftfile /var/lib/chrony/chrony.drift
hwclockfile /etc/adjtime
rtcdevice /dev/rtc0
rtcsync

OpenNTPD /etc/ntpd.conf

Install OpenNTPD

apk add openntpd

Add to default run level.

rc-update add openntpd default

/etc/ntpd.conf

# sample ntpd configuration file, see ntpd.conf(5)

# Addresses to listen on (ntpd does not listen by default)
listen on 192.168.1.1
listen on 192.168.2.1

# sync to a single server
#server ntp.example.org

# use a random selection of NTP Pool Time Servers
# see http://support.ntp.org/bin/view/Servers/NTPPoolServers
server 0.pool.ntp.org
server 1.pool.ntp.org
server 2.pool.ntp.org
server 3.pool.ntp.org

tlsdate

The time can also be extracted from a https handshake. If the certificate is self-signed you will need to use skip-verification:

apk add tlsdate

tlsdate -V --skip-verification -p 80 -H example.com

timezone

You might also want to set a timezone, see Setting the timezone.

Saving Time

There are two ways to do this. If you didn't buy an RTC clock see Saving time with Software Clock. If you did like the PiFace Real Time Clock see Saving time with Hardware Clock

Unbound DNS forwarder with dnscrypt

We want to be able to do our lookups using dnscrypt without installing DNSCrypt on every client on the network. DNSCrypt can use it's own protocol or DNS over HTTPS.

The router will also run a DNS forwarder and request unknown domains over DNSCrypt for our clients. Borrowed from the ArchLinux wiki article on dnscrypt-proxy.

Unbound

First install

apk add unbound

/etc/unbound/unbound.conf

server:
    # Use this to include other text into the file.
    include: "/etc/unbound/filter.conf"

    # verbosity number, 0 is least verbose. 1 is default.
    verbosity: 1

    # specify the interfaces to answer queries from by ip-address.
    # The default is to listen to localhost (127.0.0.1 and ::1).
    # specify 0.0.0.0 and ::0 to bind to all available interfaces.
    # specify every interface[@port] on a new 'interface:' labelled line.
    # The listen interfaces are not changed on reload, only on restart.
    interface: 192.168.2.1
    interface: 192.168.3.1

    # Enable IPv4, "yes" or "no".
    do-ip4: yes

    # Enable IPv6, "yes" or "no".
    do-ip6: yes

    # Enable UDP, "yes" or "no".
    do-udp: yes

    # Enable TCP, "yes" or "no".
    do-tcp: yes

    # control which clients are allowed to make (recursive) queries
    # to this server. Specify classless netblocks with /size and action.
    # By default everything is refused, except for localhost.
    # Choose deny (drop message), refuse (polite error reply),
    # allow (recursive ok), allow_setrd (recursive ok, rd bit is forced on),
    # allow_snoop (recursive and nonrecursive ok)
    # deny_non_local (drop queries unless can be answered from local-data)
    # refuse_non_local (like deny_non_local but polite error reply).
    # access-control: 0.0.0.0/0 refuse
    # access-control: 127.0.0.0/8 allow
    # access-control: ::0/0 refuse
    # access-control: ::1 allow
    # access-control: ::ffff:127.0.0.1 allow
    access-control: 192.168.1.0/24 allow
    access-control: 192.168.2.0/24 allow
    access-control: 192.168.3.0/24 allow

    # the log file, "" means log to stderr.
    # Use of this option sets use-syslog to "no".
    logfile: "/var/log/unbound/unbound.log"

    # Log to syslog(3) if yes. The log facility LOG_DAEMON is used to
    # log to. If yes, it overrides the logfile.
    use-syslog: no

    # print one line with time, IP, name, type, class for every query.
    # log-queries: no

    # print one line per reply, with time, IP, name, type, class, rcode,
    # timetoresolve, fromcache and responsesize.
    # log-replies: no

    # enable to not answer id.server and hostname.bind queries.
    hide-identity: yes

    # enable to not answer version.server and version.bind queries.
    # hide-version: yes

    # enable to not answer trustanchor.unbound queries.
    hide-trustanchor: yes


    # Harden against very small EDNS buffer sizes.
    harden-short-bufsize: yes

    # Harden against unseemly large queries.
    harden-large-queries: yes

    # Harden against out of zone rrsets, to avoid spoofing attempts.
    harden-glue: yes

    # Harden against receiving dnssec-stripped data. If you turn it
    # off, failing to validate dnskey data for a trustanchor will
    # trigger insecure mode for that zone (like without a trustanchor).
    # Default on, which insists on dnssec data for trust-anchored zones.
    harden-dnssec-stripped: yes

    # Harden against queries that fall under dnssec-signed nxdomain names.
    harden-below-nxdomain: yes

    # Harden the referral path by performing additional queries for
    # infrastructure data.  Validates the replies (if possible).
    # Default off, because the lookups burden the server.  Experimental
    # implementation of draft-wijngaards-dnsext-resolver-side-mitigation.
    # harden-referral-path: no

    # Harden against algorithm downgrade when multiple algorithms are
    # advertised in the DS record.  If no, allows the weakest algorithm
    # to validate the zone.
    harden-algo-downgrade: yes

    # Use 0x20-encoded random bits in the query to foil spoof attempts.
    # This feature is an experimental implementation of draft dns-0x20.
    use-caps-for-id: yes

    # Allow the domain (and its subdomains) to contain private addresses.
    # local-data statements are allowed to contain private addresses too.
    private-domain: "<HOSTNAME>"

    # if yes, the above default do-not-query-address entries are present.
    # if no, localhost can be queried (for testing and debugging).
    do-not-query-localhost: no

    # File with trusted keys, kept uptodate using RFC5011 probes,
    # initial file like trust-anchor-file, then it stores metadata.
    # Use several entries, one per domain name, to track multiple zones.
    #
    # If you want to perform DNSSEC validation, run unbound-anchor before
    # you start unbound (i.e. in the system boot scripts).  And enable:
    # Please note usage of unbound-anchor root anchor is at your own risk
    # and under the terms of our LICENSE (see that file in the source).
    # auto-trust-anchor-file: "@UNBOUND_ROOTKEY_FILE@"
    auto-trust-anchor-file: "/etc/unbound/root.key"

    # If unbound is running service for the local host then it is useful
    # to perform lan-wide lookups to the upstream, and unblock the
    # long list of local-zones above.  If this unbound is a dns server
    # for a network of computers, disabled is better and stops information
    # leakage of local lan information.
    unblock-lan-zones: no

    # If you configure local-data without specifying local-zone, by
    # default a transparent local-zone is created for the data.
    #
    # You can add locally served data with
    # local-zone: "local." static
    # local-data: "mycomputer.local. IN A 192.0.2.51"
    # local-data: 'mytext.local TXT "content of text record"'

    # request upstream over TLS (with plain DNS inside the TLS stream).
    # Default is no.  Can be turned on and off with unbound-control.
    # tls-upstream: no

    # Forward zones
    # Create entries like below, to make all queries for 'example.com' and
    # 'example.org' go to the given list of servers. These servers have to handle
    # recursion to other nameservers. List zero or more nameservers by hostname
    # or by ipaddress. Use an entry with name "." to forward all queries.
    # If you enable forward-first, it attempts without the forward if it fails.
    # forward-zone:
    #    name: "example.com"
    #    forward-addr: 192.0.2.68
    #    forward-addr: 192.0.2.73@5355  # forward to port 5355.
    #    forward-first: no
    #    forward-tls-upstream: no
    #    forward-no-cache: no
    # forward-zone:
    #    name: "example.org"
    #    forward-host: fwd.example.com

forward-zone:
    name: "."
    forward-addr: 172.16.32.1@53
    forward-addr: ::1@53000
    forward-addr: 127.0.0.1@53000

Blocking Microsoft Telemetry on the network by domain

Microsoft has added telemetry analytics to Windows which you may want to block at a network level. More information about that can be found here.

This script takes in a list of domains and produces a filter file. We are directing all lookups to "0.0.0.1" which is an invalid IP and should fail immediately, unlike localhost. There are lists of the addresses in various places such as the tools people use to do this locally on Windows, ie Destroy-Windows-10-Spying, DisableWinTracking, Debloat-Windows-10 and Dominator.Windows10. I have prepared the list further down: Linux Router with VPN on a Raspberry Pi#/etc/unbound/filter.conf.

You could also use this to block advertising, but that's probably easier to do in a web browser with something like uBlock Origin.

Another way is to disable this stuff with a group policy see Manage connections from Windows operating system components to Microsoft services only for Windows 10 Enterprise, version 1607 and newer and Windows Server 2016.

/etc/unbound/unbound.conf

In your main unbound configuration add

include: /etc/unbound/filter.conf

Script to prepare/sort domains for Unbound

#!/bin/sh

##################################################
# Script taken from http://npr.me.uk/unbound.html
# Note you need GNU sed
##################################################

# Remove "#" comments
# Remove space and tab
# Remove blank lines
# Remove localhost and broadcasthost lines
# Keep just the hosts
# Remove leading and trailing space and tab (again)
# Make everything lower case

sed -e "s/#.*//" \
    -e "s/[ \x09]*$//"\
    -e "/^$/ d" \
    -e "/^.*local.*/ d" \
    -e "/^.*broadcasthost.*/ d" \
    -e "s/\(^.*\) \([a-zA-Z0-9\.\-]*\)/\2/" \
    -e "s/^[ \x09]*//;s/[ \x09]*$//" $1 \
    -e "s/\(.*\)/\L\1/" hosts.txt > temp1.txt

# Remove any duplicate hosts

sort temp1.txt | uniq >temp2.txt

# Remove any hosts starting with "."
# Create the two required lines for each host.

sed -e "/^\..*/ d" \
    -e "s/\(^.*\)/local-zone: \x22\1\x22 redirect\nlocal-data: \x22\1 A 0.0.0.1\x22/" \
       temp2.txt > filter.conf

# Clean up
rm temp1.txt
rm temp2.txt

/etc/unbound/filter.conf

local-zone: "a-0001.a-msedge.net" redirect
local-data: "a-0001.a-msedge.net A 0.0.0.1"
local-zone: "a-0001.dc-msedge.net" redirect
local-data: "a-0001.dc-msedge.net A 0.0.0.1"
local-zone: "a-0002.a-msedge.net" redirect
local-data: "a-0002.a-msedge.net A 0.0.0.1"
local-zone: "a-0003.a-msedge.net" redirect
local-data: "a-0003.a-msedge.net A 0.0.0.1"
local-zone: "a-0004.a-msedge.net" redirect
local-data: "a-0004.a-msedge.net A 0.0.0.1"
local-zone: "a-0005.a-msedge.net" redirect
local-data: "a-0005.a-msedge.net A 0.0.0.1"
local-zone: "a-0006.a-msedge.net" redirect
local-data: "a-0006.a-msedge.net A 0.0.0.1"
local-zone: "a-0007.a-msedge.net" redirect
local-data: "a-0007.a-msedge.net A 0.0.0.1"
local-zone: "a-0008.a-msedge.net" redirect
local-data: "a-0008.a-msedge.net A 0.0.0.1"
local-zone: "a-0009.a-msedge.net" redirect
local-data: "a-0009.a-msedge.net A 0.0.0.1"
local-zone: "a-0010.a-msedge.net" redirect
local-data: "a-0010.a-msedge.net A 0.0.0.1"
local-zone: "a-0011.a-msedge.net" redirect
local-data: "a-0011.a-msedge.net A 0.0.0.1"
local-zone: "a-0012.a-msedge.net" redirect
local-data: "a-0012.a-msedge.net A 0.0.0.1"
local-zone: "a.ads1.msn.com" redirect
local-data: "a.ads1.msn.com A 0.0.0.1"
local-zone: "a.ads2.msads.net" redirect
local-data: "a.ads2.msads.net A 0.0.0.1"
local-zone: "a.ads2.msn.com" redirect
local-data: "a.ads2.msn.com A 0.0.0.1"
local-zone: "ac3.msn.com" redirect
local-data: "ac3.msn.com A 0.0.0.1"
local-zone: "activity.windows.com" redirect
local-data: "activity.windows.com A 0.0.0.1"
local-zone: "adnexus.net" redirect
local-data: "adnexus.net A 0.0.0.1"
local-zone: "adnxs.com" redirect
local-data: "adnxs.com A 0.0.0.1"
local-zone: "ads1.msads.net" redirect
local-data: "ads1.msads.net A 0.0.0.1"
local-zone: "ads1.msn.com" redirect
local-data: "ads1.msn.com A 0.0.0.1"
local-zone: "ads.msn.com" redirect
local-data: "ads.msn.com A 0.0.0.1"
local-zone: "aidps.atdmt.com" redirect
local-data: "aidps.atdmt.com A 0.0.0.1"
local-zone: "aka-cdn-ns.adtech.de" redirect
local-data: "aka-cdn-ns.adtech.de A 0.0.0.1"
local-zone: "a-msedge.net" redirect
local-data: "a-msedge.net A 0.0.0.1"
local-zone: "a.rad.msn.com" redirect
local-data: "a.rad.msn.com A 0.0.0.1"
local-zone: "array101-prod.do.dsp.mp.microsoft.com" redirect
local-data: "array101-prod.do.dsp.mp.microsoft.com A 0.0.0.1"
local-zone: "array102-prod.do.dsp.mp.microsoft.com" redirect
local-data: "array102-prod.do.dsp.mp.microsoft.com A 0.0.0.1"
local-zone: "array103-prod.do.dsp.mp.microsoft.com" redirect
local-data: "array103-prod.do.dsp.mp.microsoft.com A 0.0.0.1"
local-zone: "array104-prod.do.dsp.mp.microsoft.com" redirect
local-data: "array104-prod.do.dsp.mp.microsoft.com A 0.0.0.1"
local-zone: "array201-prod.do.dsp.mp.microsoft.com" redirect
local-data: "array201-prod.do.dsp.mp.microsoft.com A 0.0.0.1"
local-zone: "array202-prod.do.dsp.mp.microsoft.com" redirect
local-data: "array202-prod.do.dsp.mp.microsoft.com A 0.0.0.1"
local-zone: "array203-prod.do.dsp.mp.microsoft.com" redirect
local-data: "array203-prod.do.dsp.mp.microsoft.com A 0.0.0.1"
local-zone: "array204-prod.do.dsp.mp.microsoft.com" redirect
local-data: "array204-prod.do.dsp.mp.microsoft.com A 0.0.0.1"
local-zone: "array401-prod.do.dsp.mp.microsoft.com" redirect
local-data: "array401-prod.do.dsp.mp.microsoft.com A 0.0.0.1"
local-zone: "array402-prod.do.dsp.mp.microsoft.com" redirect
local-data: "array402-prod.do.dsp.mp.microsoft.com A 0.0.0.1"
local-zone: "array403-prod.do.dsp.mp.microsoft.com" redirect
local-data: "array403-prod.do.dsp.mp.microsoft.com A 0.0.0.1"
local-zone: "array404-prod.do.dsp.mp.microsoft.com" redirect
local-data: "array404-prod.do.dsp.mp.microsoft.com A 0.0.0.1"
local-zone: "array405-prod.do.dsp.mp.microsoft.com" redirect
local-data: "array405-prod.do.dsp.mp.microsoft.com A 0.0.0.1"
local-zone: "array406-prod.do.dsp.mp.microsoft.com" redirect
local-data: "array406-prod.do.dsp.mp.microsoft.com A 0.0.0.1"
local-zone: "array407-prod.do.dsp.mp.microsoft.com" redirect
local-data: "array407-prod.do.dsp.mp.microsoft.com A 0.0.0.1"
local-zone: "array408-prod.do.dsp.mp.microsoft.com" redirect
local-data: "array408-prod.do.dsp.mp.microsoft.com A 0.0.0.1"
local-zone: "ars.smartscreen.microsoft.com" redirect
local-data: "ars.smartscreen.microsoft.com A 0.0.0.1"
local-zone: "az361816.vo.msecnd.net" redirect
local-data: "az361816.vo.msecnd.net A 0.0.0.1"
local-zone: "az512334.vo.msecnd.net" redirect
local-data: "az512334.vo.msecnd.net A 0.0.0.1"
local-zone: "b.ads1.msn.com" redirect
local-data: "b.ads1.msn.com A 0.0.0.1"
local-zone: "b.ads2.msads.net" redirect
local-data: "b.ads2.msads.net A 0.0.0.1"
local-zone: "bingads.microsoft.com" redirect
local-data: "bingads.microsoft.com A 0.0.0.1"
local-zone: "bl3301-a.1drv.com" redirect
local-data: "bl3301-a.1drv.com A 0.0.0.1"
local-zone: "bl3301-c.1drv.com" redirect
local-data: "bl3301-c.1drv.com A 0.0.0.1"
local-zone: "bl3301-g.1drv.com" redirect
local-data: "bl3301-g.1drv.com A 0.0.0.1"
local-zone: "blob.weather.microsoft.com" redirect
local-data: "blob.weather.microsoft.com A 0.0.0.1"
local-zone: "bn1304-e.1drv.com" redirect
local-data: "bn1304-e.1drv.com A 0.0.0.1"
local-zone: "bn1306-a.1drv.com" redirect
local-data: "bn1306-a.1drv.com A 0.0.0.1"
local-zone: "bn1306-e.1drv.com" redirect
local-data: "bn1306-e.1drv.com A 0.0.0.1"
local-zone: "bn1306-g.1drv.com" redirect
local-data: "bn1306-g.1drv.com A 0.0.0.1"
local-zone: "bn2b-cor001.api.p001.1drv.com" redirect
local-data: "bn2b-cor001.api.p001.1drv.com A 0.0.0.1"
local-zone: "bn2b-cor002.api.p001.1drv.com" redirect
local-data: "bn2b-cor002.api.p001.1drv.com A 0.0.0.1"
local-zone: "bn2b-cor003.api.p001.1drv.com" redirect
local-data: "bn2b-cor003.api.p001.1drv.com A 0.0.0.1"
local-zone: "bn2b-cor004.api.p001.1drv.com" redirect
local-data: "bn2b-cor004.api.p001.1drv.com A 0.0.0.1"
local-zone: "bn2wns1.wns.windows.com" redirect
local-data: "bn2wns1.wns.windows.com A 0.0.0.1"
local-zone: "bn3p-cor001.api.p001.1drv.com" redirect
local-data: "bn3p-cor001.api.p001.1drv.com A 0.0.0.1"
local-zone: "bn3sch020022328.wns.windows.com" redirect
local-data: "bn3sch020022328.wns.windows.com A 0.0.0.1"
local-zone: "b.rad.msn.com" redirect
local-data: "b.rad.msn.com A 0.0.0.1"
local-zone: "bs.serving-sys.com" redirect
local-data: "bs.serving-sys.com A 0.0.0.1"
local-zone: "by3301-a.1drv.com" redirect
local-data: "by3301-a.1drv.com A 0.0.0.1"
local-zone: "by3301-c.1drv.com" redirect
local-data: "by3301-c.1drv.com A 0.0.0.1"
local-zone: "by3301-e.1drv.com" redirect
local-data: "by3301-e.1drv.com A 0.0.0.1"
local-zone: "c-0001.dc-msedge.net" redirect
local-data: "c-0001.dc-msedge.net A 0.0.0.1"
local-zone: "cache.datamart.windows.com" redirect
local-data: "cache.datamart.windows.com A 0.0.0.1"
local-zone: "candycrushsoda.king.com" redirect
local-data: "candycrushsoda.king.com A 0.0.0.1"
local-zone: "c.atdmt.com" redirect
local-data: "c.atdmt.com A 0.0.0.1"
local-zone: "ca.telemetry.microsoft.com" redirect
local-data: "ca.telemetry.microsoft.com A 0.0.0.1"
local-zone: "cdn.atdmt.com" redirect
local-data: "cdn.atdmt.com A 0.0.0.1"
local-zone: "cdn.content.prod.cms.msn.com" redirect
local-data: "cdn.content.prod.cms.msn.com A 0.0.0.1"
local-zone: "cdn.onenote.net" redirect
local-data: "cdn.onenote.net A 0.0.0.1"
local-zone: "cds1204.lon.llnw.net" redirect
local-data: "cds1204.lon.llnw.net A 0.0.0.1"
local-zone: "cds1293.lon.llnw.net" redirect
local-data: "cds1293.lon.llnw.net A 0.0.0.1"
local-zone: "cds20417.lcy.llnw.net" redirect
local-data: "cds20417.lcy.llnw.net A 0.0.0.1"
local-zone: "cds20431.lcy.llnw.net" redirect
local-data: "cds20431.lcy.llnw.net A 0.0.0.1"
local-zone: "cds20450.lcy.llnw.net" redirect
local-data: "cds20450.lcy.llnw.net A 0.0.0.1"
local-zone: "cds20457.lcy.llnw.net" redirect
local-data: "cds20457.lcy.llnw.net A 0.0.0.1"
local-zone: "cds20475.lcy.llnw.net" redirect
local-data: "cds20475.lcy.llnw.net A 0.0.0.1"
local-zone: "cds21244.lon.llnw.net" redirect
local-data: "cds21244.lon.llnw.net A 0.0.0.1"
local-zone: "cds26.ams9.msecn.net" redirect
local-data: "cds26.ams9.msecn.net A 0.0.0.1"
local-zone: "cds425.lcy.llnw.net" redirect
local-data: "cds425.lcy.llnw.net A 0.0.0.1"
local-zone: "cds459.lcy.llnw.net" redirect
local-data: "cds459.lcy.llnw.net A 0.0.0.1"
local-zone: "cds494.lcy.llnw.net" redirect
local-data: "cds494.lcy.llnw.net A 0.0.0.1"
local-zone: "cds965.lon.llnw.net" redirect
local-data: "cds965.lon.llnw.net A 0.0.0.1"
local-zone: "ch1-cor001.api.p001.1drv.com" redirect
local-data: "ch1-cor001.api.p001.1drv.com A 0.0.0.1"
local-zone: "ch1-cor002.api.p001.1drv.com" redirect
local-data: "ch1-cor002.api.p001.1drv.com A 0.0.0.1"
local-zone: "ch3301-c.1drv.com" redirect
local-data: "ch3301-c.1drv.com A 0.0.0.1"
local-zone: "ch3301-e.1drv.com" redirect
local-data: "ch3301-e.1drv.com A 0.0.0.1"
local-zone: "ch3301-g.1drv.com" redirect
local-data: "ch3301-g.1drv.com A 0.0.0.1"
local-zone: "ch3302-c.1drv.com" redirect
local-data: "ch3302-c.1drv.com A 0.0.0.1"
local-zone: "ch3302-e.1drv.com" redirect
local-data: "ch3302-e.1drv.com A 0.0.0.1"
local-zone: "choice.microsoft.com" redirect
local-data: "choice.microsoft.com A 0.0.0.1"
local-zone: "choice.microsoft.com.nsatc.net" redirect
local-data: "choice.microsoft.com.nsatc.net A 0.0.0.1"
local-zone: "clientconfig.passport.net" redirect
local-data: "clientconfig.passport.net A 0.0.0.1"
local-zone: "client-s.gateway.messenger.live.com" redirect
local-data: "client-s.gateway.messenger.live.com A 0.0.0.1"
local-zone: "client.wns.windows.com" redirect
local-data: "client.wns.windows.com A 0.0.0.1"
local-zone: "c.msn.com" redirect
local-data: "c.msn.com A 0.0.0.1"
local-zone: "compatexchange1.trafficmanager.net" redirect
local-data: "compatexchange1.trafficmanager.net A 0.0.0.1"
local-zone: "compatexchange.cloudapp.net" redirect
local-data: "compatexchange.cloudapp.net A 0.0.0.1"
local-zone: "continuum.dds.microsoft.com" redirect
local-data: "continuum.dds.microsoft.com A 0.0.0.1"
local-zone: "corpext.msitadfs.glbdns2.microsoft.com" redirect
local-data: "corpext.msitadfs.glbdns2.microsoft.com A 0.0.0.1"
local-zone: "corp.sts.microsoft.com" redirect
local-data: "corp.sts.microsoft.com A 0.0.0.1"
local-zone: "cp101-prod.do.dsp.mp.microsoft.com" redirect
local-data: "cp101-prod.do.dsp.mp.microsoft.com A 0.0.0.1"
local-zone: "cp201-prod.do.dsp.mp.microsoft.com" redirect
local-data: "cp201-prod.do.dsp.mp.microsoft.com A 0.0.0.1"
local-zone: "cp401-prod.do.dsp.mp.microsoft.com" redirect
local-data: "cp401-prod.do.dsp.mp.microsoft.com A 0.0.0.1"
local-zone: "cs1.wpc.v0cdn.net" redirect
local-data: "cs1.wpc.v0cdn.net A 0.0.0.1"
local-zone: "db3aqu.atdmt.com" redirect
local-data: "db3aqu.atdmt.com A 0.0.0.1"
local-zone: "db3wns2011111.wns.windows.com" redirect
local-data: "db3wns2011111.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101100122.wns.windows.com" redirect
local-data: "db5sch101100122.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101100127.wns.windows.com" redirect
local-data: "db5sch101100127.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101100831.wns.windows.com" redirect
local-data: "db5sch101100831.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101100835.wns.windows.com" redirect
local-data: "db5sch101100835.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101100917.wns.windows.com" redirect
local-data: "db5sch101100917.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101100925.wns.windows.com" redirect
local-data: "db5sch101100925.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101100928.wns.windows.com" redirect
local-data: "db5sch101100928.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101100938.wns.windows.com" redirect
local-data: "db5sch101100938.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101001.wns.windows.com" redirect
local-data: "db5sch101101001.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101022.wns.windows.com" redirect
local-data: "db5sch101101022.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101024.wns.windows.com" redirect
local-data: "db5sch101101024.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101031.wns.windows.com" redirect
local-data: "db5sch101101031.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101034.wns.windows.com" redirect
local-data: "db5sch101101034.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101042.wns.windows.com" redirect
local-data: "db5sch101101042.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101044.wns.windows.com" redirect
local-data: "db5sch101101044.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101122.wns.windows.com" redirect
local-data: "db5sch101101122.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101123.wns.windows.com" redirect
local-data: "db5sch101101123.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101125.wns.windows.com" redirect
local-data: "db5sch101101125.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101128.wns.windows.com" redirect
local-data: "db5sch101101128.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101129.wns.windows.com" redirect
local-data: "db5sch101101129.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101133.wns.windows.com" redirect
local-data: "db5sch101101133.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101145.wns.windows.com" redirect
local-data: "db5sch101101145.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101209.wns.windows.com" redirect
local-data: "db5sch101101209.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101221.wns.windows.com" redirect
local-data: "db5sch101101221.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101228.wns.windows.com" redirect
local-data: "db5sch101101228.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101231.wns.windows.com" redirect
local-data: "db5sch101101231.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101237.wns.windows.com" redirect
local-data: "db5sch101101237.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101317.wns.windows.com" redirect
local-data: "db5sch101101317.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101324.wns.windows.com" redirect
local-data: "db5sch101101324.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101329.wns.windows.com" redirect
local-data: "db5sch101101329.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101333.wns.windows.com" redirect
local-data: "db5sch101101333.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101334.wns.windows.com" redirect
local-data: "db5sch101101334.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101338.wns.windows.com" redirect
local-data: "db5sch101101338.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101419.wns.windows.com" redirect
local-data: "db5sch101101419.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101424.wns.windows.com" redirect
local-data: "db5sch101101424.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101426.wns.windows.com" redirect
local-data: "db5sch101101426.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101427.wns.windows.com" redirect
local-data: "db5sch101101427.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101430.wns.windows.com" redirect
local-data: "db5sch101101430.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101445.wns.windows.com" redirect
local-data: "db5sch101101445.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101511.wns.windows.com" redirect
local-data: "db5sch101101511.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101519.wns.windows.com" redirect
local-data: "db5sch101101519.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101529.wns.windows.com" redirect
local-data: "db5sch101101529.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101535.wns.windows.com" redirect
local-data: "db5sch101101535.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101541.wns.windows.com" redirect
local-data: "db5sch101101541.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101543.wns.windows.com" redirect
local-data: "db5sch101101543.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101608.wns.windows.com" redirect
local-data: "db5sch101101608.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101618.wns.windows.com" redirect
local-data: "db5sch101101618.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101629.wns.windows.com" redirect
local-data: "db5sch101101629.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101631.wns.windows.com" redirect
local-data: "db5sch101101631.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101633.wns.windows.com" redirect
local-data: "db5sch101101633.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101640.wns.windows.com" redirect
local-data: "db5sch101101640.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101711.wns.windows.com" redirect
local-data: "db5sch101101711.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101722.wns.windows.com" redirect
local-data: "db5sch101101722.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101739.wns.windows.com" redirect
local-data: "db5sch101101739.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101745.wns.windows.com" redirect
local-data: "db5sch101101745.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101813.wns.windows.com" redirect
local-data: "db5sch101101813.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101820.wns.windows.com" redirect
local-data: "db5sch101101820.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101826.wns.windows.com" redirect
local-data: "db5sch101101826.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101835.wns.windows.com" redirect
local-data: "db5sch101101835.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101837.wns.windows.com" redirect
local-data: "db5sch101101837.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101844.wns.windows.com" redirect
local-data: "db5sch101101844.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101907.wns.windows.com" redirect
local-data: "db5sch101101907.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101914.wns.windows.com" redirect
local-data: "db5sch101101914.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101929.wns.windows.com" redirect
local-data: "db5sch101101929.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101939.wns.windows.com" redirect
local-data: "db5sch101101939.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101101941.wns.windows.com" redirect
local-data: "db5sch101101941.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101102015.wns.windows.com" redirect
local-data: "db5sch101102015.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101102017.wns.windows.com" redirect
local-data: "db5sch101102017.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101102019.wns.windows.com" redirect
local-data: "db5sch101102019.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101102023.wns.windows.com" redirect
local-data: "db5sch101102023.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101102025.wns.windows.com" redirect
local-data: "db5sch101102025.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101102032.wns.windows.com" redirect
local-data: "db5sch101102032.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101102033.wns.windows.com" redirect
local-data: "db5sch101102033.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101110108.wns.windows.com" redirect
local-data: "db5sch101110108.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101110109.wns.windows.com" redirect
local-data: "db5sch101110109.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101110114.wns.windows.com" redirect
local-data: "db5sch101110114.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101110135.wns.windows.com" redirect
local-data: "db5sch101110135.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101110142.wns.windows.com" redirect
local-data: "db5sch101110142.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101110204.wns.windows.com" redirect
local-data: "db5sch101110204.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101110206.wns.windows.com" redirect
local-data: "db5sch101110206.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101110214.wns.windows.com" redirect
local-data: "db5sch101110214.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101110225.wns.windows.com" redirect
local-data: "db5sch101110225.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101110232.wns.windows.com" redirect
local-data: "db5sch101110232.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101110245.wns.windows.com" redirect
local-data: "db5sch101110245.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101110315.wns.windows.com" redirect
local-data: "db5sch101110315.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101110323.wns.windows.com" redirect
local-data: "db5sch101110323.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101110325.wns.windows.com" redirect
local-data: "db5sch101110325.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101110328.wns.windows.com" redirect
local-data: "db5sch101110328.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101110331.wns.windows.com" redirect
local-data: "db5sch101110331.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101110341.wns.windows.com" redirect
local-data: "db5sch101110341.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101110343.wns.windows.com" redirect
local-data: "db5sch101110343.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101110345.wns.windows.com" redirect
local-data: "db5sch101110345.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101110403.wns.windows.com" redirect
local-data: "db5sch101110403.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101110419.wns.windows.com" redirect
local-data: "db5sch101110419.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101110438.wns.windows.com" redirect
local-data: "db5sch101110438.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101110442.wns.windows.com" redirect
local-data: "db5sch101110442.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101110501.wns.windows.com" redirect
local-data: "db5sch101110501.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101110527.wns.windows.com" redirect
local-data: "db5sch101110527.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101110533.wns.windows.com" redirect
local-data: "db5sch101110533.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101110618.wns.windows.com" redirect
local-data: "db5sch101110618.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101110622.wns.windows.com" redirect
local-data: "db5sch101110622.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101110624.wns.windows.com" redirect
local-data: "db5sch101110624.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101110626.wns.windows.com" redirect
local-data: "db5sch101110626.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101110634.wns.windows.com" redirect
local-data: "db5sch101110634.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101110705.wns.windows.com" redirect
local-data: "db5sch101110705.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101110724.wns.windows.com" redirect
local-data: "db5sch101110724.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101110740.wns.windows.com" redirect
local-data: "db5sch101110740.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101110810.wns.windows.com" redirect
local-data: "db5sch101110810.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101110816.wns.windows.com" redirect
local-data: "db5sch101110816.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101110821.wns.windows.com" redirect
local-data: "db5sch101110821.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101110822.wns.windows.com" redirect
local-data: "db5sch101110822.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101110825.wns.windows.com" redirect
local-data: "db5sch101110825.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101110828.wns.windows.com" redirect
local-data: "db5sch101110828.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101110835.wns.windows.com" redirect
local-data: "db5sch101110835.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101110919.wns.windows.com" redirect
local-data: "db5sch101110919.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101110921.wns.windows.com" redirect
local-data: "db5sch101110921.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101110923.wns.windows.com" redirect
local-data: "db5sch101110923.wns.windows.com A 0.0.0.1"
local-zone: "db5sch101110929.wns.windows.com" redirect
local-data: "db5sch101110929.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103081814.wns.windows.com" redirect
local-data: "db5sch103081814.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103082011.wns.windows.com" redirect
local-data: "db5sch103082011.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103082111.wns.windows.com" redirect
local-data: "db5sch103082111.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103082308.wns.windows.com" redirect
local-data: "db5sch103082308.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103082406.wns.windows.com" redirect
local-data: "db5sch103082406.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103082409.wns.windows.com" redirect
local-data: "db5sch103082409.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103082609.wns.windows.com" redirect
local-data: "db5sch103082609.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103082611.wns.windows.com" redirect
local-data: "db5sch103082611.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103082709.wns.windows.com" redirect
local-data: "db5sch103082709.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103082712.wns.windows.com" redirect
local-data: "db5sch103082712.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103082806.wns.windows.com" redirect
local-data: "db5sch103082806.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103090115.wns.windows.com" redirect
local-data: "db5sch103090115.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103090415.wns.windows.com" redirect
local-data: "db5sch103090415.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103090513.wns.windows.com" redirect
local-data: "db5sch103090513.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103090515.wns.windows.com" redirect
local-data: "db5sch103090515.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103090608.wns.windows.com" redirect
local-data: "db5sch103090608.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103090806.wns.windows.com" redirect
local-data: "db5sch103090806.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103090814.wns.windows.com" redirect
local-data: "db5sch103090814.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103090906.wns.windows.com" redirect
local-data: "db5sch103090906.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103091011.wns.windows.com" redirect
local-data: "db5sch103091011.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103091012.wns.windows.com" redirect
local-data: "db5sch103091012.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103091106.wns.windows.com" redirect
local-data: "db5sch103091106.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103091108.wns.windows.com" redirect
local-data: "db5sch103091108.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103091212.wns.windows.com" redirect
local-data: "db5sch103091212.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103091311.wns.windows.com" redirect
local-data: "db5sch103091311.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103091414.wns.windows.com" redirect
local-data: "db5sch103091414.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103091511.wns.windows.com" redirect
local-data: "db5sch103091511.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103091617.wns.windows.com" redirect
local-data: "db5sch103091617.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103091715.wns.windows.com" redirect
local-data: "db5sch103091715.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103091817.wns.windows.com" redirect
local-data: "db5sch103091817.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103091908.wns.windows.com" redirect
local-data: "db5sch103091908.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103091911.wns.windows.com" redirect
local-data: "db5sch103091911.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103092010.wns.windows.com" redirect
local-data: "db5sch103092010.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103092108.wns.windows.com" redirect
local-data: "db5sch103092108.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103092109.wns.windows.com" redirect
local-data: "db5sch103092109.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103092209.wns.windows.com" redirect
local-data: "db5sch103092209.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103092210.wns.windows.com" redirect
local-data: "db5sch103092210.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103092509.wns.windows.com" redirect
local-data: "db5sch103092509.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103100117.wns.windows.com" redirect
local-data: "db5sch103100117.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103100121.wns.windows.com" redirect
local-data: "db5sch103100121.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103100221.wns.windows.com" redirect
local-data: "db5sch103100221.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103100313.wns.windows.com" redirect
local-data: "db5sch103100313.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103100314.wns.windows.com" redirect
local-data: "db5sch103100314.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103100510.wns.windows.com" redirect
local-data: "db5sch103100510.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103100511.wns.windows.com" redirect
local-data: "db5sch103100511.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103100611.wns.windows.com" redirect
local-data: "db5sch103100611.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103100712.wns.windows.com" redirect
local-data: "db5sch103100712.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103101105.wns.windows.com" redirect
local-data: "db5sch103101105.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103101208.wns.windows.com" redirect
local-data: "db5sch103101208.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103101212.wns.windows.com" redirect
local-data: "db5sch103101212.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103101314.wns.windows.com" redirect
local-data: "db5sch103101314.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103101411.wns.windows.com" redirect
local-data: "db5sch103101411.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103101413.wns.windows.com" redirect
local-data: "db5sch103101413.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103101513.wns.windows.com" redirect
local-data: "db5sch103101513.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103101610.wns.windows.com" redirect
local-data: "db5sch103101610.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103101611.wns.windows.com" redirect
local-data: "db5sch103101611.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103101705.wns.windows.com" redirect
local-data: "db5sch103101705.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103101711.wns.windows.com" redirect
local-data: "db5sch103101711.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103101909.wns.windows.com" redirect
local-data: "db5sch103101909.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103101914.wns.windows.com" redirect
local-data: "db5sch103101914.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103102009.wns.windows.com" redirect
local-data: "db5sch103102009.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103102112.wns.windows.com" redirect
local-data: "db5sch103102112.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103102203.wns.windows.com" redirect
local-data: "db5sch103102203.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103102209.wns.windows.com" redirect
local-data: "db5sch103102209.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103102310.wns.windows.com" redirect
local-data: "db5sch103102310.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103102404.wns.windows.com" redirect
local-data: "db5sch103102404.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103102609.wns.windows.com" redirect
local-data: "db5sch103102609.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103102610.wns.windows.com" redirect
local-data: "db5sch103102610.wns.windows.com A 0.0.0.1"
local-zone: "db5sch103102805.wns.windows.com" redirect
local-data: "db5sch103102805.wns.windows.com A 0.0.0.1"
local-zone: "db5wns1d.wns.windows.com" redirect
local-data: "db5wns1d.wns.windows.com A 0.0.0.1"
local-zone: "db5.wns.windows.com" redirect
local-data: "db5.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102090104.wns.windows.com" redirect
local-data: "db6sch102090104.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102090112.wns.windows.com" redirect
local-data: "db6sch102090112.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102090116.wns.windows.com" redirect
local-data: "db6sch102090116.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102090122.wns.windows.com" redirect
local-data: "db6sch102090122.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102090203.wns.windows.com" redirect
local-data: "db6sch102090203.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102090206.wns.windows.com" redirect
local-data: "db6sch102090206.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102090208.wns.windows.com" redirect
local-data: "db6sch102090208.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102090209.wns.windows.com" redirect
local-data: "db6sch102090209.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102090211.wns.windows.com" redirect
local-data: "db6sch102090211.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102090305.wns.windows.com" redirect
local-data: "db6sch102090305.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102090306.wns.windows.com" redirect
local-data: "db6sch102090306.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102090308.wns.windows.com" redirect
local-data: "db6sch102090308.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102090311.wns.windows.com" redirect
local-data: "db6sch102090311.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102090313.wns.windows.com" redirect
local-data: "db6sch102090313.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102090410.wns.windows.com" redirect
local-data: "db6sch102090410.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102090412.wns.windows.com" redirect
local-data: "db6sch102090412.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102090504.wns.windows.com" redirect
local-data: "db6sch102090504.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102090510.wns.windows.com" redirect
local-data: "db6sch102090510.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102090512.wns.windows.com" redirect
local-data: "db6sch102090512.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102090513.wns.windows.com" redirect
local-data: "db6sch102090513.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102090514.wns.windows.com" redirect
local-data: "db6sch102090514.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102090519.wns.windows.com" redirect
local-data: "db6sch102090519.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102090613.wns.windows.com" redirect
local-data: "db6sch102090613.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102090619.wns.windows.com" redirect
local-data: "db6sch102090619.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102090810.wns.windows.com" redirect
local-data: "db6sch102090810.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102090811.wns.windows.com" redirect
local-data: "db6sch102090811.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102090902.wns.windows.com" redirect
local-data: "db6sch102090902.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102090905.wns.windows.com" redirect
local-data: "db6sch102090905.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102090907.wns.windows.com" redirect
local-data: "db6sch102090907.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102090908.wns.windows.com" redirect
local-data: "db6sch102090908.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102090910.wns.windows.com" redirect
local-data: "db6sch102090910.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102090911.wns.windows.com" redirect
local-data: "db6sch102090911.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102091003.wns.windows.com" redirect
local-data: "db6sch102091003.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102091007.wns.windows.com" redirect
local-data: "db6sch102091007.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102091008.wns.windows.com" redirect
local-data: "db6sch102091008.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102091009.wns.windows.com" redirect
local-data: "db6sch102091009.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102091011.wns.windows.com" redirect
local-data: "db6sch102091011.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102091103.wns.windows.com" redirect
local-data: "db6sch102091103.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102091105.wns.windows.com" redirect
local-data: "db6sch102091105.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102091204.wns.windows.com" redirect
local-data: "db6sch102091204.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102091209.wns.windows.com" redirect
local-data: "db6sch102091209.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102091305.wns.windows.com" redirect
local-data: "db6sch102091305.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102091307.wns.windows.com" redirect
local-data: "db6sch102091307.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102091308.wns.windows.com" redirect
local-data: "db6sch102091308.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102091309.wns.windows.com" redirect
local-data: "db6sch102091309.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102091314.wns.windows.com" redirect
local-data: "db6sch102091314.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102091412.wns.windows.com" redirect
local-data: "db6sch102091412.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102091503.wns.windows.com" redirect
local-data: "db6sch102091503.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102091507.wns.windows.com" redirect
local-data: "db6sch102091507.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102091602.wns.windows.com" redirect
local-data: "db6sch102091602.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102091603.wns.windows.com" redirect
local-data: "db6sch102091603.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102091606.wns.windows.com" redirect
local-data: "db6sch102091606.wns.windows.com A 0.0.0.1"
local-zone: "db6sch102091607.wns.windows.com" redirect
local-data: "db6sch102091607.wns.windows.com A 0.0.0.1"
local-zone: "deploy.static.akamaitechnologies.com" redirect
local-data: "deploy.static.akamaitechnologies.com A 0.0.0.1"
local-zone: "device.auth.xboxlive.com" redirect
local-data: "device.auth.xboxlive.com A 0.0.0.1"
local-zone: "dev.virtualearth.net" redirect
local-data: "dev.virtualearth.net A 0.0.0.1"
local-zone: "df.telemetry.microsoft.com" redirect
local-data: "df.telemetry.microsoft.com A 0.0.0.1"
local-zone: "diagnostics.support.microsoft.com" redirect
local-data: "diagnostics.support.microsoft.com A 0.0.0.1"
local-zone: "disc101-prod.do.dsp.mp.microsoft.com" redirect
local-data: "disc101-prod.do.dsp.mp.microsoft.com A 0.0.0.1"
local-zone: "disc201-prod.do.dsp.mp.microsoft.com" redirect
local-data: "disc201-prod.do.dsp.mp.microsoft.com A 0.0.0.1"
local-zone: "disc401-prod.do.dsp.mp.microsoft.com" redirect
local-data: "disc401-prod.do.dsp.mp.microsoft.com A 0.0.0.1"
local-zone: "dmd.metaservices.microsoft.com" redirect
local-data: "dmd.metaservices.microsoft.com A 0.0.0.1"
local-zone: "dns.msftncsi.com" redirect
local-data: "dns.msftncsi.com A 0.0.0.1"
local-zone: "ec.atdmt.com" redirect
local-data: "ec.atdmt.com A 0.0.0.1"
local-zone: "ecn.dev.virtualearth.net" redirect
local-data: "ecn.dev.virtualearth.net A 0.0.0.1"
local-zone: "eu.vortex.data.microsoft.com" redirect
local-data: "eu.vortex.data.microsoft.com A 0.0.0.1"
local-zone: "feedback.microsoft-hohm.com" redirect
local-data: "feedback.microsoft-hohm.com A 0.0.0.1"
local-zone: "feedback.search.microsoft.com" redirect
local-data: "feedback.search.microsoft.com A 0.0.0.1"
local-zone: "feedback.windows.com" redirect
local-data: "feedback.windows.com A 0.0.0.1"
local-zone: "flex.msn.com" redirect
local-data: "flex.msn.com A 0.0.0.1"
local-zone: "fs.microsoft.com" redirect
local-data: "fs.microsoft.com A 0.0.0.1"
local-zone: "geo-prod.do.dsp.mp.microsoft.com" redirect
local-data: "geo-prod.do.dsp.mp.microsoft.com A 0.0.0.1"
local-zone: "geover-prod.do.dsp.mp.microsoft.com" redirect
local-data: "geover-prod.do.dsp.mp.microsoft.com A 0.0.0.1"
local-zone: "g.msn.com" redirect
local-data: "g.msn.com A 0.0.0.1"
local-zone: "h1.msn.com" redirect
local-data: "h1.msn.com A 0.0.0.1"
local-zone: "h2.msn.com" redirect
local-data: "h2.msn.com A 0.0.0.1"
local-zone: "i1.services.social.microsoft.com" redirect
local-data: "i1.services.social.microsoft.com A 0.0.0.1"
local-zone: "i1.services.social.microsoft.com.nsatc.net" redirect
local-data: "i1.services.social.microsoft.com.nsatc.net A 0.0.0.1"
local-zone: "i-bl6p-cor001.api.p001.1drv.com" redirect
local-data: "i-bl6p-cor001.api.p001.1drv.com A 0.0.0.1"
local-zone: "i-by3p-cor001.api.p001.1drv.com" redirect
local-data: "i-by3p-cor001.api.p001.1drv.com A 0.0.0.1"
local-zone: "i-by3p-cor002.api.p001.1drv.com" redirect
local-data: "i-by3p-cor002.api.p001.1drv.com A 0.0.0.1"
local-zone: "i-ch1-cor001.api.p001.1drv.com" redirect
local-data: "i-ch1-cor001.api.p001.1drv.com A 0.0.0.1"
local-zone: "i-ch1-cor002.api.p001.1drv.com" redirect
local-data: "i-ch1-cor002.api.p001.1drv.com A 0.0.0.1"
local-zone: "img-s-msn-com.akamaized.net" redirect
local-data: "img-s-msn-com.akamaized.net A 0.0.0.1"
local-zone: "inference.location.live.net" redirect
local-data: "inference.location.live.net A 0.0.0.1"
local-zone: "insiderppe.cloudapp.net" redirect
local-data: "insiderppe.cloudapp.net A 0.0.0.1"
local-zone: "i-sn2-cor001.api.p001.1drv.com" redirect
local-data: "i-sn2-cor001.api.p001.1drv.com A 0.0.0.1"
local-zone: "i-sn2-cor002.api.p001.1drv.com" redirect
local-data: "i-sn2-cor002.api.p001.1drv.com A 0.0.0.1"
local-zone: "kv101-prod.do.dsp.mp.microsoft.com" redirect
local-data: "kv101-prod.do.dsp.mp.microsoft.com A 0.0.0.1"
local-zone: "kv201-prod.do.dsp.mp.microsoft.com" redirect
local-data: "kv201-prod.do.dsp.mp.microsoft.com A 0.0.0.1"
local-zone: "kv401-prod.do.dsp.mp.microsoft.com" redirect
local-data: "kv401-prod.do.dsp.mp.microsoft.com A 0.0.0.1"
local-zone: "lb1.www.ms.akadns.net" redirect
local-data: "lb1.www.ms.akadns.net A 0.0.0.1"
local-zone: "licensing.mp.microsoft.com" redirect
local-data: "licensing.mp.microsoft.com A 0.0.0.1"
local-zone: "live.rads.msn.com" redirect
local-data: "live.rads.msn.com A 0.0.0.1"
local-zone: "ls2web.redmond.corp.microsoft.com" redirect
local-data: "ls2web.redmond.corp.microsoft.com A 0.0.0.1"
local-zone: "m.adnxs.com" redirect
local-data: "m.adnxs.com A 0.0.0.1"
local-zone: "mediaredirect.microsoft.com" redirect
local-data: "mediaredirect.microsoft.com A 0.0.0.1"
local-zone: "mobile.pipe.aria.microsoft.com" redirect
local-data: "mobile.pipe.aria.microsoft.com A 0.0.0.1"
local-zone: "msedge.net" redirect
local-data: "msedge.net A 0.0.0.1"
local-zone: "msftncsi.com" redirect
local-data: "msftncsi.com A 0.0.0.1"
local-zone: "msntest.serving-sys.com" redirect
local-data: "msntest.serving-sys.com A 0.0.0.1"
local-zone: "oca.telemetry.microsoft.com" redirect
local-data: "oca.telemetry.microsoft.com A 0.0.0.1"
local-zone: "oca.telemetry.microsoft.com.nsatc.net" redirect
local-data: "oca.telemetry.microsoft.com.nsatc.net A 0.0.0.1"
local-zone: "officeclient.microsoft.com" redirect
local-data: "officeclient.microsoft.com A 0.0.0.1"
local-zone: "oneclient.sfx.ms" redirect
local-data: "oneclient.sfx.ms A 0.0.0.1"
local-zone: "pre.footprintpredict.com" redirect
local-data: "pre.footprintpredict.com A 0.0.0.1"
local-zone: "preview.msn.com" redirect
local-data: "preview.msn.com A 0.0.0.1"
local-zone: "pti.store.microsoft.com" redirect
local-data: "pti.store.microsoft.com A 0.0.0.1"
local-zone: "query.prod.cms.rt.microsoft.com" redirect
local-data: "query.prod.cms.rt.microsoft.com A 0.0.0.1"
local-zone: "rad.msn.com" redirect
local-data: "rad.msn.com A 0.0.0.1"
local-zone: "redir.metaservices.microsoft.com" redirect
local-data: "redir.metaservices.microsoft.com A 0.0.0.1"
local-zone: "register.cdpcs.microsoft.com" redirect
local-data: "register.cdpcs.microsoft.com A 0.0.0.1"
local-zone: "reports.wes.df.telemetry.microsoft.com" redirect
local-data: "reports.wes.df.telemetry.microsoft.com A 0.0.0.1"
local-zone: "s0.2mdn.net" redirect
local-data: "s0.2mdn.net A 0.0.0.1"
local-zone: "schemas.microsoft.akadns.net" redirect
local-data: "schemas.microsoft.akadns.net A 0.0.0.1"
local-zone: "search.msn.com" redirect
local-data: "search.msn.com A 0.0.0.1"
local-zone: "secure.adnxs.com" redirect
local-data: "secure.adnxs.com A 0.0.0.1"
local-zone: "secure.flashtalking.com" redirect
local-data: "secure.flashtalking.com A 0.0.0.1"
local-zone: "services.wes.df.telemetry.microsoft.com" redirect
local-data: "services.wes.df.telemetry.microsoft.com A 0.0.0.1"
local-zone: "settings.data.glbdns2.microsoft.com" redirect
local-data: "settings.data.glbdns2.microsoft.com A 0.0.0.1"
local-zone: "settings.data.microsoft.com" redirect
local-data: "settings.data.microsoft.com A 0.0.0.1"
local-zone: "settings-sandbox.data.microsoft.com" redirect
local-data: "settings-sandbox.data.microsoft.com A 0.0.0.1"
local-zone: "settings-ssl.xboxlive.com" redirect
local-data: "settings-ssl.xboxlive.com A 0.0.0.1"
local-zone: "settings-win.data.microsoft.com" redirect
local-data: "settings-win.data.microsoft.com A 0.0.0.1"
local-zone: "settings-win-ppe.data.microsoft.com" redirect
local-data: "settings-win-ppe.data.microsoft.com A 0.0.0.1"
local-zone: "sn3301-c.1drv.com" redirect
local-data: "sn3301-c.1drv.com A 0.0.0.1"
local-zone: "sn3301-e.1drv.com" redirect
local-data: "sn3301-e.1drv.com A 0.0.0.1"
local-zone: "sn3301-g.1drv.com" redirect
local-data: "sn3301-g.1drv.com A 0.0.0.1"
local-zone: "so.2mdn.net" redirect
local-data: "so.2mdn.net A 0.0.0.1"
local-zone: "spynet2.microsoft.com" redirect
local-data: "spynet2.microsoft.com A 0.0.0.1"
local-zone: "spynetalt.microsoft.com" redirect
local-data: "spynetalt.microsoft.com A 0.0.0.1"
local-zone: "spyneteurope.microsoft.akadns.net" redirect
local-data: "spyneteurope.microsoft.akadns.net A 0.0.0.1"
local-zone: "sqm.df.telemetry.microsoft.com" redirect
local-data: "sqm.df.telemetry.microsoft.com A 0.0.0.1"
local-zone: "sqm.telemetry.microsoft.com" redirect
local-data: "sqm.telemetry.microsoft.com A 0.0.0.1"
local-zone: "sqm.telemetry.microsoft.com.nsatc.net" redirect
local-data: "sqm.telemetry.microsoft.com.nsatc.net A 0.0.0.1"
local-zone: "static.2mdn.net" redirect
local-data: "static.2mdn.net A 0.0.0.1"
local-zone: "storecatalogrevocation.storequality.microsoft.com" redirect
local-data: "storecatalogrevocation.storequality.microsoft.com A 0.0.0.1"
local-zone: "storeedgefd.dsx.mp.microsoft.com" redirect
local-data: "storeedgefd.dsx.mp.microsoft.com A 0.0.0.1"
local-zone: "store-images.s-microsoft.com" redirect
local-data: "store-images.s-microsoft.com A 0.0.0.1"
local-zone: "support.microsoft.com" redirect
local-data: "support.microsoft.com A 0.0.0.1"
local-zone: "survey.watson.microsoft.com" redirect
local-data: "survey.watson.microsoft.com A 0.0.0.1"
local-zone: "t0.ssl.ak.dynamic.tiles.virtualearth.net" redirect
local-data: "t0.ssl.ak.dynamic.tiles.virtualearth.net A 0.0.0.1"
local-zone: "t0.ssl.ak.tiles.virtualearth.net" redirect
local-data: "t0.ssl.ak.tiles.virtualearth.net A 0.0.0.1"
local-zone: "telecommand.telemetry.microsoft.com" redirect
local-data: "telecommand.telemetry.microsoft.com A 0.0.0.1"
local-zone: "telecommand.telemetry.microsoft.com.nsatc.net" redirect
local-data: "telecommand.telemetry.microsoft.com.nsatc.net A 0.0.0.1"
local-zone: "telemetry.appex.bing.net" redirect
local-data: "telemetry.appex.bing.net A 0.0.0.1"
local-zone: "telemetry.microsoft.com" redirect
local-data: "telemetry.microsoft.com A 0.0.0.1"
local-zone: "telemetry.urs.microsoft.com" redirect
local-data: "telemetry.urs.microsoft.com A 0.0.0.1"
local-zone: "test.activity.windows.com" redirect
local-data: "test.activity.windows.com A 0.0.0.1"
local-zone: "tile-service.weather.microsoft.com" redirect
local-data: "tile-service.weather.microsoft.com A 0.0.0.1"
local-zone: "time.windows.com" redirect
local-data: "time.windows.com A 0.0.0.1"
local-zone: "tk2.plt.msn.com" redirect
local-data: "tk2.plt.msn.com A 0.0.0.1"
local-zone: "tsfe.trafficshaping.dsp.mp.microsoft.com" redirect
local-data: "tsfe.trafficshaping.dsp.mp.microsoft.com A 0.0.0.1"
local-zone: "urs.smartscreen.microsoft.com" redirect
local-data: "urs.smartscreen.microsoft.com A 0.0.0.1"
local-zone: "v10.vortex-win.data.metron.live.com.nsatc.net" redirect
local-data: "v10.vortex-win.data.metron.live.com.nsatc.net A 0.0.0.1"
local-zone: "v10.vortex-win.data.microsoft.com" redirect
local-data: "v10.vortex-win.data.microsoft.com A 0.0.0.1"
local-zone: "version.hybrid.api.here.com" redirect
local-data: "version.hybrid.api.here.com A 0.0.0.1"
local-zone: "view.atdmt.com" redirect
local-data: "view.atdmt.com A 0.0.0.1"
local-zone: "vortex-bn2.metron.live.com.nsatc.net" redirect
local-data: "vortex-bn2.metron.live.com.nsatc.net A 0.0.0.1"
local-zone: "vortex-cy2.metron.live.com.nsatc.net" redirect
local-data: "vortex-cy2.metron.live.com.nsatc.net A 0.0.0.1"
local-zone: "vortex.data.glbdns2.microsoft.com" redirect
local-data: "vortex.data.glbdns2.microsoft.com A 0.0.0.1"
local-zone: "vortex.data.metron.live.com.nsatc.net" redirect
local-data: "vortex.data.metron.live.com.nsatc.net A 0.0.0.1"
local-zone: "vortex.data.microsoft.com" redirect
local-data: "vortex.data.microsoft.com A 0.0.0.1"
local-zone: "vortex-db5.metron.live.com.nsatc.net" redirect
local-data: "vortex-db5.metron.live.com.nsatc.net A 0.0.0.1"
local-zone: "vortex-hk2.metron.live.com.nsatc.net" redirect
local-data: "vortex-hk2.metron.live.com.nsatc.net A 0.0.0.1"
local-zone: "vortex-sandbox.data.microsoft.com" redirect
local-data: "vortex-sandbox.data.microsoft.com A 0.0.0.1"
local-zone: "vortex-win.data.metron.live.com.nsatc.net" redirect
local-data: "vortex-win.data.metron.live.com.nsatc.net A 0.0.0.1"
local-zone: "vortex-win.data.microsoft.com" redirect
local-data: "vortex-win.data.microsoft.com A 0.0.0.1"
local-zone: "watson.microsoft.com" redirect
local-data: "watson.microsoft.com A 0.0.0.1"
local-zone: "watson.ppe.telemetry.microsoft.com" redirect
local-data: "watson.ppe.telemetry.microsoft.com A 0.0.0.1"
local-zone: "watson.telemetry.microsoft.com" redirect
local-data: "watson.telemetry.microsoft.com A 0.0.0.1"
local-zone: "watson.telemetry.microsoft.com.nsatc.net" redirect
local-data: "watson.telemetry.microsoft.com.nsatc.net A 0.0.0.1"
local-zone: "wdcpalt.microsoft.com" redirect
local-data: "wdcpalt.microsoft.com A 0.0.0.1"
local-zone: "wdcp.microsoft.com" redirect
local-data: "wdcp.microsoft.com A 0.0.0.1"
local-zone: "web.vortex.data.microsoft.com" redirect
local-data: "web.vortex.data.microsoft.com A 0.0.0.1"
local-zone: "wes.df.telemetry.microsoft.com" redirect
local-data: "wes.df.telemetry.microsoft.com A 0.0.0.1"
local-zone: "win10.ipv6.microsoft.com" redirect
local-data: "win10.ipv6.microsoft.com A 0.0.0.1"
local-zone: "win10-trt.msedge.net" redirect
local-data: "win10-trt.msedge.net A 0.0.0.1"
local-zone: "win1710.ipv6.microsoft.com" redirect
local-data: "win1710.ipv6.microsoft.com A 0.0.0.1"
local-zone: "wscont.apps.microsoft.com" redirect
local-data: "wscont.apps.microsoft.com A 0.0.0.1"
local-zone: "www.msedge.net" redirect
local-data: "www.msedge.net A 0.0.0.1"
local-zone: "www.msftconnecttest.com" redirect
local-data: "www.msftconnecttest.com A 0.0.0.1"
local-zone: "www.msftncsi.com" redirect
local-data: "www.msftncsi.com A 0.0.0.1"

DNSCrypt

Configuring DNSCrypt to send it's lookups through the VPN and not directly out your ppp interface is done using a socks proxy.

You can test that you're not getting DNS leaks by using dnsleak.com or this one from GRC. Providers like CloudFlare and Google (1.1.1.1, 8.8.8.8) use anycast which should be pointing to a server located to where your VPN exits.

/etc/dnscrypt-proxy/dnscrypt-proxy.toml

Using the sample dnscrypt config is fine, you will need to make these changes:

listen_addresses = ['127.0.0.1:53000', '[::1]:53000']
proxy = "socks5://127.0.0.1:1080"

Dante

First install dante, you'll need to pin the testing repository. See: Alpine Linux package management#Repository pinning.

apk add dante-server@testing

Configure it like so:

/etc/sockd.conf

logoutput: stderr
internal: 127.0.0.1 port = 1080
external: tun0
clientmethod: none
socksmethod: none
user.unprivileged: sockd

# Allow connections from localhost to any host
client pass {
        from: 127.0.0.1/8 to: 0.0.0.0/0
	log: error # connect/disconnect
}

# Generic pass statement - bind/outgoing traffic
socks pass {
        from: 0.0.0.0/0 to: 0.0.0.0/0
        command: bind connect udpassociate
        log: error # connect disconnect iooperation
}

# Generic pass statement for incoming connections/packets
socks pass {
        from: 0.0.0.0/0 to: 0.0.0.0/0
        command: bindreply udpreply
        log: error # connect disconnect iooperation
}

Finally the services to the the default run level:

rc-update add sockd default

rc-update add unbound default

rc-update add dnscrypt-proxy default

Random number generation

There are two ways to assist with random number generation Entropy and randomness. This can be particularly useful if you're generating your own Diffie-Hellman nonce file, used in the FreeRadius EAP-TLS configuration section. Or for that matter any process which requires lots of random number generation such as generating certificates or public private keys.

Haveged

Haveged is a great way to improve random number generation speed. It uses the unpredictable random number generator based upon an adaptation of the HAVEGE algorithm.

Install haveged:

apk add haveged

Start haveged service:

service haveged start

Add service to boot

rc-update add haveged default

Start rngd service:

service haveged start

Add service to boot:

rc-update add haveged default

rng-tools with bcm2708-rng

Pre Alpine Linux 3.8 (which includes rngd 5)

All Raspberry Pis come with the bcm2708-rng random number generator on board. If you are doing this project on a Raspberry Pi then you may choose to use this also.

Add the kernel module to /etc/modules:

echo "bcm2708-rng" > /etc/modules

Insert module:

modprobe bcm2708-rng

Install rng-tools:

apk add rng-tools

Set the random device (/dev/random) and rng device (/dev/hwrng) in /etc/conf.d/rngd

RNGD_OPTS="--no-drng=1 --no-tpm=1 -o /dev/random -r /dev/hwrng"

Post Alpine Linux 3.8 (which includes rngd 6)

With AlpineLinux 3.8 you don't have to insert the module as it is already built in the kernel.

Additionally the syntax has changed for rngd so for /etc/conf.d/rngd you'll need

RNGD_OPTS="-x1 -o /dev/random -r /dev/hwrng"

Start rngd service:

service rngd start

Add service to boot:

rc-update add rngd default

You can test it with:

cat /dev/hwrng | rngtest -c 1000

You should see something like:

rngtest 5
Copyright (c) 2004 by Henrique de Moraes Holschuh
This is free software; see the source for copying conditions.  There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

rngtest: starting FIPS tests...
rngtest: bits received from input: 20000032
rngtest: FIPS 140-2 successes: 1000
rngtest: FIPS 140-2 failures: 0
rngtest: FIPS 140-2(2001-10-10) Monobit: 0
rngtest: FIPS 140-2(2001-10-10) Poker: 0
rngtest: FIPS 140-2(2001-10-10) Runs: 0
rngtest: FIPS 140-2(2001-10-10) Long run: 0
rngtest: FIPS 140-2(2001-10-10) Continuous run: 0
rngtest: input channel speed: (min=117.709; avg=808.831; max=3255208.333)Kibits/s
rngtest: FIPS tests speed: (min=17.199; avg=22.207; max=22.653)Mibits/s
rngtest: Program run time: 25178079 microseconds

It's possible you might have a some failures. That's okay, two runs I did previously had a failure each.

WiFi 802.1x EAP and FreeRadius

A more secure way than using pre-shared keys (WPA2) is to use EAP-TLS and use separate certificates for each device. See FreeRadius EAP-TLS configuration

VPN Tunnel on specific subnet

As mentioned earlier in this article it might be useful to have a VPN subnet and a non-VPN subnet. Typically gaming consoles or computers might want low-latency connections. For this exercise we use fwmark.

We expand the network to look like this:

Network Diagram with IPv4 tunnel

Install the necessary packages:

apk add openvpn iproute2 iputils

/etc/modules

You'll want to add the tun module

tun

/etc/iproute2/rt_tables

Add the two routing tables to the bottom of rt_tables. It should look something like this:

#
# reserved values
#
255	local
254	main
253	default
0	unspec
#
# local
#
#1	inr.ruhep
1 ISP
2 VPN

/etc/network/interfaces

Next up add the virtual interface (really just a IP address to eth0) eth0:2, just under eth0 will do.

# Route to VPN subnet
auto eth0:2
iface eth0:2 inet static
  address 192.168.2.1
  netmask 255.255.255.0
  broadcast 192.168.2.255
  post-up /etc/network/fwmark_rules

/etc/sysctl.d/local.conf

If you want to use fwmark rules you need to change this setting. It causes the router to still do source validation.

# Needed to use fwmark
net.ipv4.conf.all.rp_filter = 2

fwmark won't work if you have this set to 1.

/etc/network/fwmark_rules

In this file we want to put the fwmark rules and set the correct priorities.

#!/bin/sh

# Normal packets to go direct out WAN
/sbin/ip rule add fwmark 1 table ISP prio 100

# Put packets destined into VPN when VPN is up
/sbin/ip rule add fwmark 2 table VPN prio 200

# Prevent packets from being routed out when VPN is down.
# This prevents packets from falling back to the main table
# that has a priority of 32766
/sbin/ip rule add prohibit fwmark 2 prio 300

/etc/ppp/ip-up

Next up we want to create the routes that should be run when PPP comes online. There are special hooks we can use in ip-up and ip-down to refer to the IP address, ppp man file - Scripts You can also read about them in your man file if you have ppp-doc installed.

#!/bin/sh
#
# This script is run by pppd when there's a successful ppp connection.
#

# Flush out any old rules that might be there
/sbin/ip route flush table ISP

# Add route to table from subnets on LAN
/sbin/ip route add 192.168.1.0/24 dev eth0 table ISP
/sbin/ip route add 192.168.2.0/24 dev eth0 table ISP

# Add route from IP given by ISP to the table
/sbin/ip rule add from ${IPREMOTE} table ISP prio 100

# Add a default route
/sbin/ip route add table ISP default via ${IPREMOTE} dev ${IFNAME}

/etc/ppp/ip-down

#!/bin/sh
#
# This script is run by pppd after the connection has ended.
#

# Delete the rules when we take the interface down
/sbin/ip rule del from ${IPREMOTE} table ISP prio 100

/etc/openvpn/route-up-fwmark.sh

OpenVPN needs similar routing scripts and it also has it's own special hooks that allow you to specify particular values. A full list is here OpenVPN man file - Environmental Variables

#!/bin/sh
#
# This script is run by OpenVPN when there's a successful VPN connection.
#

# Flush out any old rules that might be there
/sbin/ip route flush table VPN

# Add route to table from 192.168.2.0/24 subnet on LAN
/sbin/ip route add 192.168.2.0/24 dev eth0 table VPN

# Add route from VPN interface IP to the VPN table
/sbin/ip rule add from ${ifconfig_local} table VPN prio 200

# Add a default route
/sbin/ip route add default via ${ifconfig_local} dev ${dev} table VPN

/etc/openvpn/route-pre-down-fwmark.sh

#!/bin/sh
#
# This script is run by OpenVPN after the connection has ended
#

# Delete the rules when we take the interface down
/sbin/ip rule del from ${ifconfig_local} table VPN prio 200

What I did find was when starting and stopping the OpenVPN service if you used:

service openvpn stop

The rules in route-pre-down-fwmark.sh were not executed.

However:

/etc/init.d/openvpn stop

seemed to work correctly.

Advanced IPtables rules that allow us to route into our two routing tables

This is an expansion of the previous set of rules. It sets up NAT masquerading for the 192.168.2.0 to go through the VPN using marked packets.

I used these guides to write complete this:

#########################################################################
# Advanced routing rule set
# Uses 192.168.1.0 via ISP
#      192.168.2.0 via VPN
#
# Packets to/from 192.168.1.0/24 are marked with 0x1 and routed to ISP
# Packets to/from 192.168.2.0/24 are marked with 0x2 and routed to VPN
#
#########################################################################

#
# NAT Table
# This is where translation of packets happens and "forwarding" of ports
# to specific hosts.
#
*nat

# Set default policies for table
:PREROUTING ACCEPT [0:0]
:INPUT ACCEPT [0:0]
:OUTPUT ACCEPT [0:0]
:POSTROUTING ACCEPT [0:0]

# Port forwarding for Bittorrent
-A PREROUTING -i tun0 -p tcp -m tcp --dport 6881:6889 -j DNAT --to-destination 192.168.2.20
-A PREROUTING -i tun0 -p udp -m udp --dport 6881:6889 -j DNAT --to-destination 192.168.2.20

# Allows routing to our modem subnet so we can access the web interface
-A POSTROUTING -s 192.168.1.0/24 -d 192.168.0.1/32 -o eth1 -p tcp -m tcp --dport 80 -j MASQUERADE
-A POSTROUTING -s 192.168.2.0/24 -d 192.168.0.1/32 -o eth1 -p tcp -m tcp --dport 80 -j MASQUERADE

# Allows hosts of the network to use the VPN tunnel
-A POSTROUTING -o tun0 -j MASQUERADE

# Allows hosts of the network to use the PPP tunnel
-A POSTROUTING -o ppp0 -j MASQUERADE
COMMIT

#
# Filter Table
# This is where we decide to ACCEPT, DROP or REJECT things
#
*filter
:INPUT DROP [0:0]
:FORWARD DROP [0:0]
:OUTPUT ACCEPT [0:0]

# Create rule chain per input interface for forwarding packets
:FWD_ETH0 - [0:0]
:FWD_ETH1 - [0:0]
:FWD_PPP0 - [0:0]
:FWD_TUN0 - [0:0]

# Create rule chain per input interface for input packets (for host itself)
:IN_ETH0 - [0:0]
:IN_ETH1 - [0:0]
:IN_PPP0 - [0:0]
:IN_TUN0 - [0:0]

# Create a log drop chain
:LOG_DROP - [0:0]

# Create a reject chain
:LOG_REJECT - [0:0]

# Pass input packet to corresponding rule chain
-A INPUT -i lo -j ACCEPT
-A INPUT -i eth0 -j IN_ETH0
-A INPUT -i eth1 -j IN_ETH1
-A INPUT -i ppp0 -j IN_PPP0
-A INPUT -i tun0 -j IN_TUN0

# Track forwarded packets
-A FORWARD -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT

# Pass forwarded packet to corresponding rule chain
-A FORWARD -i eth0 -j FWD_ETH0
-A FORWARD -i eth1 -j FWD_ETH1
-A FORWARD -i ppp0 -j FWD_PPP0
-A FORWARD -i tun0 -j FWD_TUN0

# Forward traffic to ISP
-A FWD_ETH0 -s 192.168.1.0/24 -j ACCEPT

# Forward traffic to VPN
-A FWD_ETH0 -s 192.168.2.0/24 -j ACCEPT

# Allow excepted server to be FORWARD to ppp0
#-A FWD_ETH0 -s 192.168.2.0/24 -d <IP_OF_EXCEPTED_SERVER>/32 -o ppp0 -j ACCEPT

# Forward SSH packets from network to modem
-A FWD_ETH1 -s 192.168.0.1/32 -d 192.168.1.0/24 -p tcp -m tcp --sport 22 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
-A FWD_ETH1 -s 192.168.0.1/32 -d 192.168.2.0/24 -p tcp -m tcp --sport 22 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT

# Forward HTTP packets from network to modem
-A FWD_ETH1 -s 192.168.0.1/32 -d 192.168.1.0/24 -p tcp -m tcp --sport 80 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
-A FWD_ETH1 -s 192.168.0.1/32 -d 192.168.2.0/24 -p tcp -m tcp --sport 80 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT

# Forward Bittorrent Port to workstation
-A FWD_TUN0 -d 192.168.2.20/32 -p tcp -m tcp --dport 6881:6889 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
-A FWD_TUN0 -d 192.168.2.20/32 -p udp -m udp --dport 6881:6889 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT

# SSH to Router
-A IN_ETH0 -s 192.168.1.0/24 -p tcp -m tcp --dport 22 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
-A IN_ETH0 -s 192.168.2.0/24 -p tcp -m tcp --dport 22 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT

# DNS to Router
-A IN_ETH0 -s 192.168.1.0/24 -p udp -m udp --dport 53 -m conntrack --ctstate NEW -j ACCEPT
-A IN_ETH0 -s 192.168.2.0/24 -p udp -m udp --dport 53 -m conntrack --ctstate NEW -j ACCEPT

# FreeRadius Client (eg a UniFi AP)
-A IN_ETH0 -s 192.168.1.0/24 -p tcp -m tcp --dport 1812 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
-A IN_ETH0 -s 192.168.1.0/24 -p udp -m udp --dport 1812 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT

# Ubiquiti UAP Device Discovery Broadcast
-A IN_ETH0 -s 192.168.1.0/24 -p udp -m udp --dport 10001 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT

# NTP to Router
-A IN_ETH0 -s 192.168.1.0/24 -p udp -m udp --dport 123 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
-A IN_ETH0 -s 192.168.2.0/24 -p udp -m udp --dport 123 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT

# Accept traffic to router on both subnets
-A IN_ETH0 -s 192.168.1.0/24 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
-A IN_ETH0 -s 192.168.2.0/24 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT

# Allow excepted server to be INPUT to eth0 from LAN
#-A IN_ETH0 -s 192.168.2.0/24 -d <IP_OF_EXCEPTED_SERVER>/32 -o ppp0 -j ACCEPT

# SSH To Modem from Router
-A IN_ETH1 -s 192.168.0.1/32 -d 192.168.0.0/30 -p tcp -m tcp --sport 22 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT

# HTTP To Modem from Router
-A IN_ETH1 -s 192.168.0.1/32 -d 192.168.0.0/30 -p tcp -m tcp --sport 80 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT

# Accept incoming tracked PPP0 connection
-A IN_PPP0 -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT

# Log dropped packets coming in on PPP0
-A IN_PPP0 -j LOG --log-prefix "DROP:INPUT " --log-level 6
-A IN_PPP0 -j LOG_DROP

# Accept incoming tracked TUN0 connection
-A IN_TUN0 -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT

# Log dropped packets coming in on TUN0
-A IN_TUN0 -j LOG --log-prefix "DROP:INPUT " --log-level 6
-A IN_TUN0 -j LOG_DROP
COMMIT

#
# Mangle Table
# This is the place where our markings happen, whether they be 0x1 or 0x2
#
*mangle

# Set default policies for table
:PREROUTING ACCEPT [0:0]
:INPUT ACCEPT [0:0]
:FORWARD ACCEPT [0:0]
:OUTPUT ACCEPT [0:0]
:POSTROUTING ACCEPT [0:0]

# Restore CONNMARK to the MARK (If one doesn't exist then no mark is set)
-A PREROUTING -j CONNMARK --restore-mark --nfmask 0xffffffff --ctmask 0xffffffff

# If packet MARK is 2, then it means there is already a connection mark and the
# original packet came in on VPN
-A PREROUTING -s 192.168.2.0/24 -m mark --mark 0x2 -j ACCEPT

# Check exception (this is a server which when accessed on a 192.168.2.0/24 address will go out the ISP table) are 0x1
#-A PREROUTING -s 192.168.2.0/24 -d <IP_OF_EXCEPTED_SERVER>/32 -m mark --mark 0x1 -j ACCEPT

# Mark packets coming from 192.168.2.0/24 are 0x2
-A PREROUTING -s 192.168.2.0/24 -j MARK --set-xmark 0x2/0xffffffff

# If packet MARK is 1, then it means there is already a connection mark and the
# original packet came in on ISP
-A PREROUTING -s 192.168.1.0/24 -m mark --mark 0x1 -j ACCEPT

# Mark packets 192.168.1.0/24 are 0x1
-A PREROUTING -s 192.168.1.0/24 -j MARK --set-xmark 0x1/0xffffffff

# Mark exception (this is a server which when accessed on a 192.168.2.0/24 address will go out the ISP table) as 0x1
#-A PREROUTING -s 192.168.2.0/24 -d <IP_OF_EXCEPTED_SERVER>/32 -j MARK --set-xmark 0x1/0xffffffff

# Set mark to 0 - This is for the modem. Otherwise it will mark with 0x1 or 0x2
-A PREROUTING -d 192.168.0.1/32 -j MARK --set-xmark 0x0/0xffffffff

# Save MARK to CONNMARK (remember iproute can't see CONNMARKs)
-A PREROUTING -j CONNMARK --save-mark --nfmask 0xffffffff --ctmask 0xffffffff
COMMIT

You may want to delete certain rules here that do not apply to you, eg the FreeRadius rules. That is covered later in this article.

OpenVPN Routing

Usually when you connect with OpenVPN the remote VPN server will push routes down to your system. We don't want this as we still want to be able to access the internet without the VPN. We have also created our own routes that we want to use earlier in this guide.

You'll need to add this to the bottom of your OpenVPN configuration file:

# Prevents default gateway from being set on the default routing table
route-noexec

# Allows route-up script to be executed
script-security 2

# Calls custom shell script after connection to add necessary routes
route-up /etc/openvpn/route-up-fwmark.sh
route-pre-down /etc/openvpn/route-pre-down-fwmark.sh

My VPNs are arranged like this in /etc/openvpn:

OpenVPN configuration file for that server:

countrycode.serverNumber.openvpn.conf

OpenVPN certs for that server:

countrycode.serverNumber.openvpn/countrycode.serverNumber.openvpn.crt
countrycode.serverNumber.openvpn/countrycode.serverNumber.openvpn.key
countrycode.serverNumber.openvpn/myKey.crt
countrycode.serverNumber.openvpn/myKey.key

So I use this helpful script to automate the process of changing between servers:

#!/bin/sh

vpn_server_filename=$1

rm /etc/openvpn/openvpn.conf
ln -s $vpn_server_filename /etc/openvpn/openvpn.conf
chown -R openvpn:openvpn /etc/openvpn
chmod -R a=-rwx,u=+rX /etc/openvpn
chmod u=x /etc/openvpn/*.sh*

if grep -Fxq "#CustomStuffHere" openvpn.conf
then
    echo "Not adding custom routes, this server has been used previously"
else
    echo "Adding custom route rules"
cat <<EOF >> /etc/openvpn/openvpn.conf

#CustomStuffHere
# Prevents default gateway from being set on the default routing table
route-noexec

# Allows route-up script to be executed
script-security 2

# Calls custom shell script after connection to add necessary routes
route-up /etc/openvpn/route-up-fwmark.sh
route-pre-down /etc/openvpn/route-pre-down-fwmark.sh

# Logging of OpenVPN to file
#log /etc/openvpn/openvpn.log
EOF

fi
echo "Remember to set BitTorrent port forward in VPN control panel"

That way I can simply change between servers by running:

changevpn.sh countrycode.serverNumber.openvpn

and then restart openvpn. I am also reminded to put the port forward through on the VPN control panel so my BitTorrent client is connectable:

service openvpn restart

Finally add openvpn to the default run level

rc-update add openvpn default

Creating a LAN only Subnet

In this section, we'll be creating a LAN only subnet. This subnet will be 192.168.3.0/24. The idea of this subnet is nodes in it cannot have their packets forwarded to the Internet, however they can be accessed via the other LAN subnets 192.168.1.0/24 and 192.168.2.0/24. This approach doesn't use VLANs although that would be recommended if you had a managed switch. The idea of this subnet is for things like WiFi access points, IP Phones which contact a local Asterisk server and of course printers.

At the end of this section we will have something like:

Network Diagram LAN ONLY Route with IPv4

/etc/iproute2/rt_tables

First up we'll add a third routing table:

3 LAN

/etc/network/interfaces

Add a an extra virtual interface (really just a IP address to eth0).

# LAN Only
auto eth0:3
iface eth0:3 inet static
  address 192.168.3.1
  netmask 255.255.255.0
  broadcast 192.168.3.255
  post-up /etc/network/route_LAN

/etc/network/route_LAN

This file will have our route added to it

#!/bin/sh

# Add routes from ISP to LAN
/sbin/ip route add 192.168.1.0/24 dev eth0 table LAN

# Add route from VPN to LAN
/sbin/ip route add 192.168.2.0/24 dev eth0 table LAN

# Add route from LAN to it's own table
/sbin/ip route add 192.168.3.0/24 dev eth0 table LAN

/etc/ppp/ip-up

Append a route from the LAN subnet to the ISP table

# Add route to LAN subnet
/sbin/ip route add 192.168.3.0/24 dev eth0 table ISP

/etc/openvpn/route-up-fwmark.sh

Append a route from the LAN subnet to the VPN table

# Add route to LAN only subnet
/sbin/ip route add 192.168.3.0/24 dev eth0 table VPN

/etc/ntpd.conf

Add a listen address for ntp (OpenNTPD).

You should now have:

# Addresses to listen on (ntpd does not listen by default)
listen on 192.168.1.1
listen on 192.168.2.1
listen on 192.168.3.1

Devices needing the correct time will need to use this NTP server because they will not be able to get it from the Internet.

Blocking bogons

Our LAN now has 4 subnets in total that are possible:

  • 192.168.0.0/30 (connection between modem and router)
  • 192.168.1.0/24 (ISP table, directly routed out WAN)
  • 192.168.2.0/24 (VPN table, routed out VPN)
  • 192.168.3.0/24 (Null routed subnet for LAN only hosts)
  • 172.16.32.0/20 (VPN provider's network, so we can access things on the VPN's network).

Everything else should be rejected. No packets should ever be forwarded on 192.168.5.2 or 10.0.0.5 for example.

Installing ipset

Install ipset:

apk add ipset

Add it to start up:

rc-update add ipset default

Now we need to load the lists of addresses into ipset Securing Your Server using IPset and Dynamic Blocklists mentions a script which was particularly useful. This script could be run on a cron job if you wanted to regularly update it and for the full bogon list you should as they change when that address space has been allocated.

For the purpose of this we will be using just the bogon-bn-nonagg.txt list.

0.0.0.0/8
10.0.0.0/8
100.64.0.0/10
127.0.0.0/8
169.254.0.0/16
172.16.0.0/12
192.0.0.0/24
192.0.2.0/24
192.168.0.0/16
198.18.0.0/15
198.51.100.0/24
203.0.113.0/24
224.0.0.0/4
240.0.0.0/4

This is unlikely to change as it's the IPV4 Reserved IP addresses space. The script:

#! /bin/bash

# /usr/local/sbin/fullbogons-ipv4
# BoneKracker
# Rev. 11 October 2012
# Tested with ipset 6.13

# Purpose: Periodically update an ipset used in a running firewall to block
# bogons. Bogons are addresses that nobody should be using on the public
# Internet because they are either private, not to be assigned, or have
# not yet been assigned.
#
# Notes: Call this from crontab. Feed updated every 4 hours.

# target="http://www.team-cymru.org/Services/Bogons/fullbogons-ipv4.txt"
# Use alternative URL from pfSense, due to 404 error with URL above
target="https://files.pfsense.org/lists/bogon-bn-nonagg.txt"
ipset_params="hash:net"

filename=$(basename ${target})
firewall_ipset=${filename%.*}           # ipset will be filename minus ext
data_dir="/var/tmp/${firewall_ipset}"   # data directory will be same
data_file="${data_dir}/${filename}"

# if data directory does not exist, create it
mkdir -pm 0750 ${data_dir}

# function to get modification time of the file in log-friendly format
get_timestamp() {
    date -r $1 +%m/%d' '%R
}

# file modification time on server is preserved during wget download
[ -w ${data_file} ] && old_timestamp=$(get_timestamp ${data_file})

# fetch file only if newer than the version we already have
wget -qNP ${data_dir} ${target}

if [ "$?" -ne "0" ]; then
    logger -p cron.err "IPSet: ${firewall_ipset} wget failed."
    exit 1
fi

timestamp=$(get_timestamp ${data_file})

# compare timestamps because wget returns success even if no newer file
if [ "${timestamp}" != "${old_timestamp}" ]; then

    temp_ipset="${firewall_ipset}_temp"
    ipset create ${temp_ipset} ${ipset_params}

    #sed -i '/^#/d' ${data_file}            # strip comments
    sed -ri '/^[#< \t]|^$/d' ${data_file}   # occasionally the file has been xhtml

    while read network; do
        ipset add ${temp_ipset} ${network}
    done < ${data_file}

    # if ipset does not exist, create it
    ipset create -exist ${firewall_ipset} ${ipset_params}

    # swap the temp ipset for the live one
    ipset swap ${temp_ipset} ${firewall_ipset}
    ipset destroy ${temp_ipset}

    # log the file modification time for use in minimizing lag in cron schedule
    logger -p cron.notice "IPSet: ${firewall_ipset} updated (as of: ${timestamp})."

fi

Now you should see the list loaded into memory when you do:

ipset list

We want to save it so our router can refer to it next time it starts up so for that:

/etc/init.d/ipset save

Adding our allowed networks

IPv4

ipset create allowed-nets-ipv4 hash:net,iface family inet

Then you can add each of your allowed networks:

ipset add allowed-nets-ipv4 192.168.0.0/30,eth1
ipset add allowed-nets-ipv4 192.168.1.0/24,eth0
ipset add allowed-nets-ipv4 192.168.2.0/24,eth0
ipset add allowed-nets-ipv4 192.168.3.0/24,eth0
ipset add allowed-nets-ipv4 127.0.0.0/8,lo
ipset add allowed-nets-ipv4 172.16.32.0/20,tun0

IPv6

For IPv6 if you've got any Unique local address ranges you may choose to add them:

ipset create allowed-nets-ipv6 hash:net,iface family inet6

ipset add allowed-nets-ipv6 fde4:8dba:82e1::/48,tun0
ipset add allowed-nets-ipv6 fde4:8dba:82e1:ffff::/64,eth0


Finally save the sets with this command so they can be loaded next boot:

/etc/init.d/ipset save

Restricting our LAN subnet with iptables, and blocking the bogons

Finally we can apply our iptables rules, to filter both 192.168.3.0/24 and make sure that subnets like 192.168.5.0/24 are not forwarded or accessible by our router. You will need to review these rules, and remove the ones that do not apply to you.

Don't forget to change your RADIUS rules if you moved your WiFi APs into the 192.168.3.0/24 subnet. You'll also need to edit /etc/raddb/clients.conf

I used a new table here called "raw". This table is more primitive than the filter table. It cannot have FORWARD rules or INPUT rules. Therefore you will still need a FORWARD rule in your filter table to block bogons originating from your LAN.

The only kind of rules we may use here are PREROUTING and OUTPUT. The OUTPUT rules will only filter traffic originating from our router's local processes, such as if we ran the ping command to a bogon range on the router's command prompt.

Traffic passes over the raw table, before connecting marking as indicated by this packet flow map: Netfilter packet flow graph this means we don't have to strip the mark off the bogon range in the mangle table anymore.

#########################################################################
# Advanced routing rule set
# Uses 192.168.1.0 via ISP
#      192.168.2.0 via VPN
#      192.168.3.0 via LAN
#
# Packets to/from 192.168.1.0/24 are marked with 0x1 and routed to ISP
# Packets to/from 192.168.2.0/24 are marked with 0x2 and routed to VPN
# Packets to/from 192.168.3.0/24 are routed to LAN and not forwarded onto
#                                    the internet
#
#########################################################################

#
# Raw Table
# This table is the place where we drop all illegal packets from networks that
# do not exist
#
*raw
:PREROUTING ACCEPT [0:0]
:OUTPUT ACCEPT [0:0]

# Create a log drop chain
:LOG_DROP_BOGON - [0:0]

# Create an output chain
:OUT_PPP0 - [0:0]
:OUT_TUN0 - [0:0]

# Allows traffic from VPN tunnel
-A PREROUTING -s 172.16.32.0/20 -i tun0 -j ACCEPT

# Allows traffic to VPN tunnel
-A PREROUTING -d 172.16.32.0/20 -j ACCEPT

# Block specified bogons coming in from ISP and VPN
# (unlikely to happen as they filter them on their router)
-A PREROUTING -i ppp0 -m set --match-set bogon-bn-nonagg src -j LOG_DROP_BOGON
-A PREROUTING -i tun0 -m set --match-set bogon-bn-nonagg src -j LOG_DROP_BOGON

# Allows my excepted ranges.
-A PREROUTING -m set --match-set allowed-nets-ipv4 src,src -j ACCEPT

# Pass output interface to corresponding chain
-A OUTPUT -o ppp0 -j OUT_PPP0
-A OUTPUT -o tun0 -j OUT_TUN0

# Log drop chain
-A LOG_DROP_BOGON -j LOG --log-prefix "Dropped Bogon (ipv4) : " --log-level 6
-A LOG_DROP_BOGON -j DROP

# Block packets originating from the router destined to bogon ranges
-A OUT_PPP0 -m set --match-set bogon-bn-nonagg dst -j LOG_DROP_BOGON

# Blocks packets originating from the router destined to bogon ranges
-A OUT_TUN0 -d 172.16.32.0/20 -j ACCEPT
-A OUT_TUN0 -m set --match-set bogon-bn-nonagg dst -j LOG_DROP_BOGON
COMMIT

#
# NAT Table
# This is where translation of packets happens and "forwarding" of ports
# to specific hosts.
#
*nat
:PREROUTING ACCEPT [0:0]
:INPUT ACCEPT [0:0]
:OUTPUT ACCEPT [0:0]
:POSTROUTING ACCEPT [0:0]

# Port forwarding for Bittorrent
-A PREROUTING -i tun0 -p tcp -m tcp --dport 6881:6889 -j DNAT --to-destination 192.168.2.20
-A PREROUTING -i tun0 -p udp -m udp --dport 6881:6889 -j DNAT --to-destination 192.168.2.20

# Allows routing to our modem subnet so we can access the web interface
-A POSTROUTING -s 192.168.1.0/24 -d 192.168.0.1/32 -o eth1 -p tcp -m tcp --dport 80 -j MASQUERADE
-A POSTROUTING -s 192.168.2.0/24 -d 192.168.0.1/32 -o eth1 -p tcp -m tcp --dport 80 -j MASQUERADE

# Allows hosts of the network to use the VPN tunnel
-A POSTROUTING -o tun0 -j MASQUERADE

# Allows hosts of the network to use the PPP tunnel
-A POSTROUTING -o ppp0 -j MASQUERADE
COMMIT

#
# Filter Table
# This is where we decide to ACCEPT, DROP or REJECT things
#
*filter
:INPUT DROP [0:0]
:FORWARD DROP [0:0]
:OUTPUT ACCEPT [0:0]

# Create rule chain per input interface for forwarding packets
:FWD_ETH0 - [0:0]
:FWD_ETH1 - [0:0]
:FWD_PPP0 - [0:0]
:FWD_TUN0 - [0:0]

# Create rule chain per input interface for input packets (for host itself)
:IN_ETH0 - [0:0]
:IN_ETH1 - [0:0]
:IN_PPP0 - [0:0]
:IN_TUN0 - [0:0]

# Create a drop chain
:LOG_DROP - [0:0]

# Create a log drop chain
:LOG_DROP_BOGON - [0:0]

# Create a reject chain
:LOG_REJECT_LANONLY - [0:0]

# Create an output chain
:OUT_PPP0 - [0:0]
:OUT_TUN0 - [0:0]

# Pass input packet to corresponding rule chain
-A INPUT -i lo -j ACCEPT
-A INPUT -i eth0 -j IN_ETH0
-A INPUT -i eth1 -j IN_ETH1
-A INPUT -i ppp0 -j IN_PPP0
-A INPUT -i tun0 -j IN_TUN0

# Track forwarded packets
-A FORWARD -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT

# Pass forwarded packet to corresponding rule chain
-A FORWARD -i eth0 -j FWD_ETH0
-A FORWARD -i eth1 -j FWD_ETH1
-A FORWARD -i ppp0 -j FWD_PPP0
-A FORWARD -i tun0 -j FWD_TUN0

# Pass output interface to corresponding chain
-A OUTPUT -o ppp0 -j OUT_PPP0
-A OUTPUT -o tun0 -j OUT_TUN0

# Forward traffic to Modem
-A FWD_ETH0 -d 192.168.0.1/32 -j ACCEPT

# Allow routing to remote address on VPN
-A FWD_ETH0 -s 192.168.1.0/24 -d 172.16.32.1/32 -o tun0 -j ACCEPT
-A FWD_ETH0 -s 192.168.2.0/24 -d 172.16.32.1/32 -o tun0 -j ACCEPT

# Allow forwarding from LAN hosts to LAN ONLY subnet
-A FWD_ETH0 -s 192.168.1.0/24 -d 192.168.3.0/24 -j ACCEPT
-A FWD_ETH0 -s 192.168.2.0/24 -d 192.168.3.0/24 -j ACCEPT

# Allow LAN ONLY subnet to contact other LAN hosts
-A FWD_ETH0 -s 192.168.3.0/24 -d 192.168.1.0/24 -j ACCEPT
-A FWD_ETH0 -s 192.168.3.0/24 -d 192.168.2.0/24 -j ACCEPT

# Refuse to forward bogons to the internet!
-A FWD_ETH0 -m set --match-set bogon-bn-nonagg dst -j LOG_DROP_BOGON

# Forward traffic to ISP
-A FWD_ETH0 -s 192.168.1.0/24 -j ACCEPT

# Forward traffic to VPN
-A FWD_ETH0 -s 192.168.2.0/24 -j ACCEPT

# Prevent 192.168.3.0/24 from accessing internet
-A FWD_ETH0 -s 192.168.3.0/24 -j LOG_REJECT_LANONLY

# Allow excepted server to be FORWARD to ppp0
#-A FWD_ETH0 -s 192.168.2.0/24 -d <IP_OF_EXCEPTED_SERVER>/32 -o ppp0 -j ACCEPT

# Forward SSH packets from network to modem
-A FWD_ETH1 -s 192.168.0.1/32 -d 192.168.1.0/24 -p tcp -m tcp --sport 22 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
-A FWD_ETH1 -s 192.168.0.1/32 -d 192.168.2.0/24 -p tcp -m tcp --sport 22 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT

# Forward HTTP packets from network to mode
-A FWD_ETH1 -s 192.168.0.1/32 -d 192.168.1.0/24 -p tcp -m tcp --sport 80 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
-A FWD_ETH1 -s 192.168.0.1/32 -d 192.168.2.0/24 -p tcp -m tcp --sport 80 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT

# Forward Bittorrent Port to workstation
-A FWD_TUN0 -d 192.168.2.20/32 -p tcp -m tcp --dport 6881:6889 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
-A FWD_TUN0 -d 192.168.2.20/32 -p udp -m udp --dport 6881:6889 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT

# SSH to Router
-A IN_ETH0 -s 192.168.1.0/24 -p tcp -m tcp --dport 22 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
-A IN_ETH0 -s 192.168.2.0/24 -p tcp -m tcp --dport 22 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT

# DNS to Router
-A IN_ETH0 -s 192.168.1.0/24 -p udp -m udp --dport 53 -m conntrack --ctstate NEW -j ACCEPT
-A IN_ETH0 -s 192.168.2.0/24 -p udp -m udp --dport 53 -m conntrack --ctstate NEW -j ACCEPT

# FreeRadius Client (eg a UniFi AP)
-A IN_ETH0 -s 192.168.3.10/32 -p tcp -m tcp --dport 1812 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
-A IN_ETH0 -s 192.168.3.10/32 -p udp -m udp --dport 1812 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT

# Ubiquiti UAP Device Discovery Broadcast
-A IN_ETH0 -s 192.168.3.10/32 -p udp -m udp --dport 10001 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT

# NTP to Router
-A IN_ETH0 -s 192.168.1.0/24 -p udp -m udp --dport 123 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
-A IN_ETH0 -s 192.168.2.0/24 -p udp -m udp --dport 123 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
-A IN_ETH0 -s 192.168.3.0/24 -p udp -m udp --dport 123 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT

# Accept traffic to router on both subnets
-A IN_ETH0 -s 192.168.1.0/24 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
-A IN_ETH0 -s 192.168.2.0/24 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT

# Allow excepted server to be INPUT to eth0 from LAN
#-A IN_ETH0 -s 192.168.2.0/24 -d <IP_OF_EXCEPTED_SERVER>/32 -o ppp0 -j ACCEPT

# SSH To Modem from Router
-A IN_ETH1 -s 192.168.0.1/32 -d 192.168.0.0/30 -p tcp -m tcp --sport 22 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT

# HTTP To Modem from Router
-A IN_ETH1 -s 192.168.0.1/32 -d 192.168.0.0/30 -p tcp -m tcp --sport 80 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT

# Accept incoming tracked PPP0 connection
-A IN_PPP0 -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT

# Log dropped packets coming in on PPP0
-A IN_PPP0 -j LOG --log-prefix "DROP:INPUT (ipv4) " --log-level 6
-A IN_PPP0 -j LOG_DROP

# Accept incoming tracked TUN0 connection
-A IN_TUN0 -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT

# Log dropped packets coming in on TUN0
-A IN_TUN0 -j LOG --log-prefix "DROP:INPUT (ipv4) " --log-level 6
-A IN_TUN0 -j LOG_DROP

# Log dropped bogons that never got forwarded
-A LOG_DROP_BOGON -j LOG --log-prefix "Dropped Bogon forward (ipv4) " --log-level 6
-A LOG_DROP_BOGON -j DROP

# Log rejected packets
-A LOG_REJECT_LANONLY -j LOG --log-prefix "Rejected packet from LAN only range : " --log-level 6
-A LOG_REJECT_LANONLY -j REJECT --reject-with icmp-port-unreachable
COMMIT

#
# Mangle Table
# This is the place where our markings happen, whether they be 0x1 or 0x2
#
*mangle

# Set default policies for table
:PREROUTING ACCEPT [0:0]
:INPUT ACCEPT [0:0]
:FORWARD ACCEPT [0:0]
:OUTPUT ACCEPT [0:0]
:POSTROUTING ACCEPT [0:0]

# Restore CONNMARK to the MARK (If one doesn't exist then no mark is set)
-A PREROUTING -j CONNMARK --restore-mark --nfmask 0xffffffff --ctmask 0xffffffff

# If packet MARK is 2, then it means there is already a connection mark and the
# original packet came in on VPN
-A PREROUTING -s 192.168.2.0/24 -m mark --mark 0x2 -j ACCEPT

# Check exception (this is a server which when accessed on a 192.168.2.0/24 address will go out the ISP table) are 0x1
#-A PREROUTING -s 192.168.2.0/24 -d <IP_OF_EXCEPTED_SERVER>/32 -m mark --mark 0x1 -j ACCEPT

# Mark packets coming from 192.168.2.0/24 are 0x2
-A PREROUTING -s 192.168.2.0/24 -j MARK --set-xmark 0x2/0xffffffff

# If packet MARK is 1, then it means there is already a connection mark and the
# original packet came in on ISP
-A PREROUTING -s 192.168.1.0/24 -m mark --mark 0x1 -j ACCEPT

# Mark packets 192.168.1.0/24 are 0x1
-A PREROUTING -s 192.168.1.0/24 -j MARK --set-xmark 0x1/0xffffffff

# Mark exception (this is a server which when accessed on a 192.168.2.0/24 address will go out the ISP table) as 0x1
#-A PREROUTING -s 192.168.2.0/24 -d <IP_OF_EXCEPTED_SERVER>/32 -j MARK --set-xmark 0x1/0xffffff

# Strip mark if packet is destined for modem
-A PREROUTING -d 192.168.0.1/32 -j MARK --set-xmark 0x0/0xffffffff

# Save MARK to CONNMARK (remember iproute can't see CONNMARKs)
-A PREROUTING -j CONNMARK --save-mark --nfmask 0xffffffff --ctmask 0xffffffff
COMMIT

Other Tips

Diagnosing firewall problems

netcat, netcat6

Netcat can be useful for testing if a port is open or closed or filtered.

apk add netcat-openbsd

After installing netcat we can use it like this:

Say we wanted to test for IPv6, UDP, Port 547 we would do this on the router:

nc -6 -u -l 547

and then this on the client to connect to it:

nc -u -v -6 2001:0db8:1234:0001::1 547

tcpdump

tcpdump can also be useful for dumping the contents of packets coming in on an interface:

apk add tcpdump

Then we can run it. This example captures all DNS traffic originating from 192.168.2.20.

tcpdump -i eth0 udp and src 192.168.2.20 and port 53

You can write the file out with the -w option, and view it in Wireshark locally on your computer. You can increase the verbosity with the -v option. Using -vv will be even more verbose. -vvv will show even more.

lbu cache

Configure lbu cache so that you don't need to download packages when you restart your router eg Local APK cache

This is particularly important as some of the images do not contain ppp-pppoe. This might mean you're unable to get an internet connection to download the other packages on boot.

lbu encryption /etc/lbu/lbu.conf

In /etc/lbu/lbu.conf you might want to enable encryption to protect your VPN keys.

# what cipher to use with -e option
DEFAULT_CIPHER=aes-256-cbc

# Uncomment the row below to encrypt config by default
ENCRYPTION=$DEFAULT_CIPHER

# Uncomment below to avoid <media> option to 'lbu commit'
# Can also be set to 'floppy'
LBU_MEDIA=mmcblk0p1

# Set the LBU_BACKUPDIR variable in case you prefer to save the apkovls
# in a normal directory instead of mounting an external media.
# LBU_BACKUPDIR=/root/config-backups

# Uncomment below to let lbu make up to 3 backups
# BACKUP_LIMIT=3

Remember to set a root password, by default Alpine Linux's root account is passwordless.

passwd root

Backup apkprov

It's a good idea to back up your apk provision file. You can pull it off your router to your local workstation with:

scp -r root@192.168.2.1:/media/mmcblk0p1/<YOUR HOST NAME>.apkovl.tar.gz.aes-256-cbc ./

And decrypt it with:

openssl enc -d -aes-256-cbc -in <YOUR HOST NAME>.apkovl.tar.gz.aes-256-cbc -out <YOUR HOST NAME>.apkovl.tar.gz

It can be encrypted with:

openssl aes-256-cbc -salt -in <YOUR HOST NAME>.apkovl.tar.gz -out <YOUR HOST NAME>.apkovl.tar.gz.aes-256-cbc

Harden SSH

Generate a SSH key

ssh-keygen -t rsa -b 4096

You will want to put the contents of id_rsa.pub in /etc/ssh/authorized_keys

You can put multiple public keys on multiple lines if more than one person has access to the router.

/etc/ssh/sshd_config

A couple of good options to set in here can be:

ListenAddress 192.168.1.1
ListenAddress 192.168.2.1

While this isn't usually a good idea, a router doesn't need more than one user.

PermitRootLogin yes

The most important options:

RSAAuthentication yes
PubkeyAuthentication yes
AuthorizedKeysFile  /etc/ssh/authorized_keys
PasswordAuthentication no
PermitEmptyPasswords no
AllowTcpForwarding no
X11Forwarding no

/etc/conf.d/sshd

You will want to add

rc_need="net"

This instructs OpenRC to make sure the network is up before starting ssh.

Finally add sshd to the default run level

rc-update add sshd default


Additionally you may want to look at Secure Secure Shell and tighten OpenSSH's cryptography options.

References