feat: support multiple zt network joins

feat: add ZT_BRIDGE to control bridge functionality

docker-compose.yml

@@ -14,6 +14,7 @@ services:
     volumes:
       - zt_config:/var/lib/zerotier-one
     environment:
-      - ZT_NETWORK=NETWORK_ID_HERE
+      - ZT_NETWORKS=NETWORK_ID_1 NETWORK_ID_2 NETWORK_ID_3
+      - ZT_BRIDGE=true
 volumes:
   zt_config:

entrypoint.sh

@@ -14,24 +14,36 @@ do
   sleep 1
 done
 
-#echo "joining networks: $ZT_NETWORK"
+# Set IPTables to allow NATting
+sysctl -w net.ipv4.ip_forward=1 > /dev/null
 
-echo "joining $ZT_NETWORK"
+echo "joining networks: $ZT_NETWORKS"
 
-while ! zerotier-cli join "$ZT_NETWORK"
+for n in $ZT_NETWORKS
 do
-    echo "joining $ZT_NETWORK failed; trying again in 1s"
+  echo "joining $n"
+
+  while ! zerotier-cli join "$n"
+  do 
+    echo "joining $n failed; trying again in 1s"
     sleep 1
+  done
+
+  if [ "$ZT_BRIDGE" = "true" ]
+  then
+    echo "iptables on $(zerotier-cli get $n portDeviceName)"
+    PHY_IFACE=eth0; ZT_IFACE=$(zerotier-cli get $n portDeviceName)
+
+    iptables -t nat -A POSTROUTING -o $PHY_IFACE -j MASQUERADE
+    iptables -A FORWARD -i $PHY_IFACE -o $ZT_IFACE -m state --state RELATED,ESTABLISHED -j ACCEPT
+    iptables -A FORWARD -i $ZT_IFACE -o $PHY_IFACE -j ACCEPT
+  fi
 done
+
+# Give ZT a second realise it's online
+sleep 10
+
 # Print Client Info
 echo "$(zerotier-cli info)"
 
-# Set IPTables to allow NATting
-sysctl -w net.ipv4.ip_forward=1 > /dev/null
-PHY_IFACE=eth0; ZT_IFACE=$(ls /sys/class/net | grep ^zt)
-
-iptables -t nat -A POSTROUTING -o $PHY_IFACE -j MASQUERADE
-iptables -A FORWARD -i $PHY_IFACE -o $ZT_IFACE -m state --state RELATED,ESTABLISHED -j ACCEPT
-iptables -A FORWARD -i $ZT_IFACE -o $PHY_IFACE -j ACCEPT
-
 sleep infinity