Provided by: shorewall_4.4.26.1-1_all bug


       tunnels - Shorewall VPN definition file




       The tunnels file is used to define rules for encapsulated (usually encrypted) traffic to
       pass between the Shorewall system and a remote gateway. Traffic flowing through the tunnel
       is handled using the normal zone/policy/rule mechanism. See for details.

       The columns in the file are as follows.

       TYPE -
           Types are as follows:

                       6to4 or 6in4  - 6to4 or 6in4 tunnel. The 6in4 synonym was added in 4.4.24.
                       ipsec         - IPv4 IPSEC
                       ipsecnat      - IPv4 IPSEC with NAT Traversal (UDP port 4500 encapsulation)
                       ipip          - IPv4 encapsulated in IPv4 (Protocol 4)
                       gre           - Generalized Routing Encapsulation (Protocol 47)
                       l2tp          - Layer 2 Tunneling Protocol (UDP port 1701)
                       pptpclient    - PPTP Client runs on the firewall
                       pptpserver    - PPTP Server runs on the firewall
                       openvpn       - OpenVPN in point-to-point mode
                       openvpnclient - OpenVPN client runs on the firewall
                       openvpnserver - OpenVPN server runs on the firewall
                       generic       - Other tunnel type

           If the type is ipsec, it may be followed by :ah to indicate that the Authentication
           Headers protocol (51) is used by the tunnel (the default is :noah which means that
           protocol 51 is not used). NAT traversal is only supported with ESP (protocol 50) so
           ipsecnat tunnels don't allow the ah option (ipsecnat:noah may be specified but is

           If type is openvpn, openvpnclient or openvpnserver it may optionally be followed by
           ":" and tcp or udp to specify the protocol to be used. If not specified, udp is

           If type is openvpn, openvpnclient or openvpnserver it may optionally be followed by
           ":" and the port number used by the tunnel. if no ":" and port number are included,
           then the default port of 1194 will be used. . Where both the protocol and port are
           specified, the protocol must be given first (e.g., openvpn:tcp:4444).

           If type is generic, it must be followed by ":" and a protocol name (from
           /etc/protocols) or a protocol number. If the protocol is tcp or udp (6 or 17), then it
           may optionally be followed by ":" and a port number.

           Comments may be attached to Netfilter rules generated from entries in this file
           through the use of COMMENT lines. These lines begin with the word COMMENT; the
           remainder of the line is treated as a comment which is attached to subsequent rules
           until another COMMENT line is found or until the end of the file is reached. To stop
           adding comments to rules, use a line with only the word COMMENT.

       ZONE - zone
           The zone of the physical interface through which tunnel traffic passes. This is
           normally your internet zone.

       GATEWAY - address-or-range
           The IP address of the remote tunnel gateway. If the remote gateway has no fixed
           address (Road Warrior) then specify the gateway as May be specified as a
           network address and if your kernel and iptables include iprange match support then IP
           address ranges are also allowed.

       GATEWAY ZONES (gateway_zone) - [zone[,zone]...]
           Optional. If the gateway system specified in the third column is a standalone host
           then this column should contain a comma-separated list of the names of the zones that
           the host might be in. This column only applies to IPSEC tunnels where it enables
           ISAKMP traffic to flow through the tunnel to the remote gateway.


       Example 1:
           IPSec tunnel.

           The remote gateway is and the remote subnet is The tunnel
           does not use the AH protocol

                       #TYPE           ZONE    GATEWAY
                       ipsec:noah      net

       Example 2:
           Road Warrior (LapTop that may connect from anywhere) where the "gw" zone is used to
           represent the remote LapTop

                       #TYPE           ZONE    GATEWAY         GATEWAY ZONES
                       ipsec           net       gw

       Example 3:
           Host is a standalone system connected via an ipsec tunnel to the firewall
           system. The host is in zone gw.

                       #TYPE           ZONE    GATEWAY         GATEWAY ZONES
                       ipsec           net     gw

       Example 4:
           Road Warriors that may belong to zones vpn1, vpn2 or vpn3. The FreeS/Wan _updown
           script will add the host to the appropriate zone using the shorewall add command on
           connect and will remove the host from the zone at disconnect time.

                       #TYPE           ZONE    GATEWAY         GATEWAY ZONES
                       ipsec           net       vpn1,vpn2,vpn3

       Example 5:
           You run the Linux PPTP client on your firewall and connect to server

                       #TYPE           ZONE    GATEWAY         GATEWAY ZONES
                       pptpclient      net

       Example 6:
           You run a PPTP server on your firewall.

                       #TYPE           ZONE    GATEWAY         GATEWAY ZONES
                       pptpserver      net

       Example 7:
           OPENVPN tunnel. The remote gateway is and openvpn uses port 7777.

                       #TYPE           ZONE    GATEWAY         GATEWAY ZONES
                       openvpn:7777    net

       Example 8:
           You have a tunnel that is not one of the supported types. Your tunnel uses UDP port
           4444. The other end of the tunnel is

                       #TYPE            ZONE    GATEWAY         GATEWAY ZONES
                       generic:udp:4444 net




       shorewall(8), shorewall-accounting(5), shorewall-actions(5), shorewall-blacklist(5),
       shorewall-hosts(5), shorewall_interfaces(5), shorewall-ipsets(5), shorewall-maclist(5),
       shorewall-masq(5), shorewall-nat(5), shorewall-netmap(5), shorewall-params(5),
       shorewall-policy(5), shorewall-providers(5), shorewall-proxyarp(5),
       shorewall-route_rules(5), shorewall-routestopped(5), shorewall-rules(5),
       shorewall.conf(5), shorewall-secmarks(5), shorewall-tcclasses(5), shorewall-tcdevices(5),
       shorewall-tcrules(5), shorewall-tos(5), shorewall-zones(5)

[FIXME: source]                             12/13/2011                       SHOREWALL-TUNNELS(5)