diff --git a/docs/FAQ.xml b/docs/FAQ.xml index cf907db67..4378dfc53 100644 --- a/docs/FAQ.xml +++ b/docs/FAQ.xml @@ -109,9 +109,9 @@ the sample configurations. Answer: Beginning with - Shorewall 4.0, the samples are in the shorewall-common package and are + Shorewall 4.4, the samples are in the shorewall package and are installed in /usr/share/doc/shorewall-common/examples/. + class="directory">/usr/share/doc/shorewall/examples/. @@ -313,8 +313,9 @@ DNAT net:address loc:local-IP-address + must be the IP address of the firewall's interface to that system + unless you use the hack described in FAQ + 1f). @@ -337,7 +338,7 @@ DNAT net:address loc:local-IP-address your DNAT rule doesn't match the connection request in some other way. In that case, you may have to use a packet - sniffer such as tcpdump or ethereal to further diagnose the + sniffer such as tcpdump or Wireshark to further diagnose the problem. @@ -399,9 +400,9 @@ DNAT net loc:192.168.1.3:22 tcp 1022 Answer courtesy of Ryan: Assume that the IP address of your local firewall interface is 192.168.1.1. - If you configure SSHD to only listen on that interface and add the - following rule then from the net, you will have 4104 listening, from - your LAN, port 22. + If you configure SSHD to only listen on that address and add the + following rule, then you will have access on port 4104 from the net + and on port 22 from your LAN. #ACTION SOURCE DEST PROTO DEST PORT(S) DNAT net fw:192.168.1.1:22 tcp 4104 @@ -448,7 +449,7 @@ DNAT net loc:192.168.1.4 tcp 21 - 206.1 - This results in the following set of events: + This results in the following sequence of events: @@ -486,7 +487,7 @@ DNAT net loc:192.168.1.4 tcp 21 - 206.1 /etc/shorewall/masq:#INTERFACE SOURCE ADDRESS PROTO PORT eth1:192.168.1.4 0.0.0.0/0 192.168.1.1 tcp 21 - This rule has the undesirable side effect that it makes all FTP + This rule has the undesirable side effect of making all FTP connections from the net appear to the FTP server as if they originated on the Shorewall system. But it will force the FTP server to reply back through the Shorewall system who can then rewrite the @@ -652,8 +653,8 @@ DNAT net net:192.168.4.22 tcp 80,443 - < If you really want to route traffic between two internal systems through your firewall, then proceed as described below. - All traffic redirected through use of this hack will look to - the server as if it originated on the firewall rather than on the + All traffic redirected through use of this technique will look + to the server as if it originated on the firewall rather than on the original client! So the server's access logs will be useless for determining which local hosts are accessing the server. @@ -679,8 +680,9 @@ loc eth1 detect routeback Note: The technique described here is known as hairpinning NAT and is described in section 6 of RFC - 4787. There it is required that the external IP - address be used as the source: + 4787. In that RFC, it is required that the + external IP address be used as the + source: #INTERFACE SOURCE ADDRESS PROTO PORT(S) eth1:192.168.1.5 eth1 130.151.100.69 tcp www @@ -720,7 +722,7 @@ DNAT loc loc:192.168.1.5 tcp www - - + If you run Shorewall-lite on your firewall, you must use the following in the firewall's configuration directory params file: @@ -759,8 +761,8 @@ DNAT loc loc:192.168.1.5 tcp www - - If you don't like those solutions and prefer, incredibly, to - route all Z->Z traffic through your firewall then: + If you don't like those solutions and prefer to route all + Z->Z traffic through your firewall then: @@ -791,7 +793,7 @@ dmz eth2 192.168.2.255 routeback #INTERFACE SOURCE ADDRESS eth2 eth2 192.168.2.254 - Like the silly hack in FAQ 2 above, this will make all + Like the technique in FAQ 2 above, this will make all dmz->dmz traffic appear to originate on the firewall. @@ -826,11 +828,9 @@ dmz eth2 192.168.2.255 routeback If your external IP address is dynamic, then you must do the following: - In /etc/shorewall/params (or in your - <export directory>/init file if you are - using Shorewall Lite on the firewall system): + In /etc/shorewall/params: - ETH0_IP=`find_first_interface_address eth0` + ETH0_IP=`find_first_interface_address eth0` and make your DNAT rule: @@ -855,6 +855,12 @@ DNAT loc dmz:192.168.2.4 tcp 80 - + + + If you use Shorewall-lite, then you need to configure the + params file in the firewall's configuration directory as described + above. +