README.md

@@ -20,69 +20,102 @@
 See http://kb.linuxvirtualserver.org/wiki/Using_arp_announce/arp_ignore_to_disable_ARP
     
 ### Setup Scripts
-These are functional setup scripts that make the application run as intended on Linux. They should later be split into
-component parts, or incorporated into the main application.
+These are functional setup scripts that make the application run as intended on Linux.
 
-#### Remote Portal
+### Remote Portal
+#### Pre-Start
 
     #!/bin/bash
     set -e
-    
-    # IPv4 Forwarding
+
+    ## Set up variables
+    REMOTE_PORTAL_ADDRESS=A.B.C.D
+
+    ## IPv4 Forwarding
     sysctl -w net.ipv4.ip_forward=1
     sysctl -w net.ipv4.conf.eth0.proxy_arp=1
     
-    # Tunnel addr/up
+    ## Tunnel addr/up
     ip addr add 172.19.152.2/31 dev nc0
     ip link set up nc0
     
-    # Deliberately break local routing
+    ## Transfer the local routing table to a much lower priority
     ip rule add from all table local priority 20
     ip rule del 0 || true
     
-    # Route packets to the interface but for nc to this host
-    ip rule add to 1.1.1.3 dport 1234 table local priority 9
+    ## Ports to route locally
+    ip rule add to "$REMOTE_PORTAL_ADDRESS" dport 1234 table local priority 1
+    ip rule add to "$REMOTE_PORTAL_ADDRESS" dport 22   table local priority 2
+
+#### Post-Start
+
+    #!/bin/bash
+    set -e
+
+    ## Set up variables
+    REMOTE_PORTAL_ADDRESS=A.B.C.D
     
     # Route packets to the interface but not for nc via the tunnel
-    ip route flush 10
-    ip route add table 10 to 1.1.1.3 via 172.19.152.3 dev nc0
-    ip rule add to 1.1.1.3 table 10 priority 10
+    ip route flush 19
+    ip route add table 19 to "$REMOTE_PORTAL_ADDRESS" via 172.19.152.3 dev nc0
+    ip rule add to "$REMOTE_PORTAL_ADDRESS" table 19 priority 19
     
-#### Local Portal
+### Local Portal
+#### Pre-Start
+
+    #!/bin/bash
+    set -e
+
+    ## Set up variables
+    GATEWAY_INTERFACE=eth0
+    GATEWAY_ADDRESS=10.36.12.1
+    
+    ## Fix ARP
+    sysctl -w net.ipv4.conf.all.arp_announce=1
+    sysctl -w net.ipv4.conf.all.arp_ignore=1
+    
+    ## IPv4 Forwarding
+    sysctl -w net.ipv4.ip_forward=1
+    
+    ## Gateway Interface Setup
+    ip addr add "$GATEWAY_ADDRESS"/32 dev "$GATEWAY_INTERFACE"
+    ip link set up "$GATEWAY_INTERFACE"
+    
+    ## Per-Interface Routing Tables
+    
+    ### 10.10.0.0/24
+    ip route flush 10
+    ip route add table 10 default via 10.10.0.1
+    ip rule add from 10.10.0.0/24 table 10 priority 10
+    
+    ### 192.168.0.0/24
+    ip route flush 11
+    ip route add table 11 default via 192.168.0.1
+    ip rule add from 192.168.0.0/24 table 11 priority 11
+
+#### Post-Start
 
     #!/bin/bash
     set -e
     
-    # Fix ARP
-    sysctl -w net.ipv4.conf.all.arp_announce=1
-    sysctl -w net.ipv4.conf.all.arp_ignore=1
+    ## Set up variables
+    REMOTE_PORTAL_ADDRESS=A.B.C.D
+    GATEWAY_INTERFACE=eth0
     
-    # IPv4 Forwarding
-    sysctl -w net.ipv4.ip_forward=1
-    
-    # Tunnel addr/up
+    ## Tunnel Address and Enable
     ip addr add 172.19.152.3/31 dev nc0
     ip link set up nc0
     
-    # Fix routing out of the correct interfaces
-    ip route flush 10
-    ip route add table 10 to 1.1.1.0/24 dev eth1
-    ip rule add from 1.1.1.4 table 10 priority 10
+    ## Route Outbound Packets Correctly
+    ip route flush 20
+    ip route add table 20 default via 172.19.152.2 dev nc0
+    ip rule add from "$REMOTE_PORTAL_ADDRESS" iif "$GATEWAY_INTERFACE" table 20 priority 20
     
-    ip route flush 11
-    ip route add table 11 to 1.1.1.0/24 dev eth2
-    ip rule add from 1.1.1.5 table 11 priority 11
-    
-    # Route packets from the remote portal's address on the client interface via the tunnel
-    ip route flush 12
-    ip route add table 12 to 1.1.1.0/24 via 172.19.152.2 dev nc0
-    ip rule add from 1.1.1.3 iif eth3 table 12 priority 12
-    
-    # Route packets to the remote portal's address out of the client interface
-    ip route flush 13
-    ip route add table 13 to 1.1.1.3 dev eth3
-    ip rule add to 1.1.1.3 table 13 priority 13
+    ## Route Inbound Packets Correctly
+    ip route flush 21
+    ip route add table 21 to "$REMOTE_PORTAL_ADDRESS" dev "$GATEWAY_INTERFACE"
+    ip rule add to "$REMOTE_PORTAL_ADDRESS" table 21 priority 21
     
 #### Client
 
-No configuration needed. Simply set the IP to that of the remote server/32 with a gateway of 192.168.1.1.
+Connect to `GATEWAY_INTERFACE` and set the IP to `REMOTE_PORTAL_ADDRESS`/32 with a gateway of `GATEWAY_ADDRESS`.