> -----Original Message----- > From: redhat-list-bounces@xxxxxxxxxx > [mailto:redhat-list-bounces@xxxxxxxxxx] On Behalf Of Pete Nesbitt > Sent: Tuesday, April 27, 2004 8:37 PM > To: frank@xxxxxxxxxxx; General Red Hat Linux discussion list > Subject: Re: [redhat] Re: Remote Desktop/Firewall > > > On April 27, 2004 07:46 pm, Frank Reichenbacher wrote: > > > -----Original Message----- > > > From: redhat-list-bounces@xxxxxxxxxx > > > [mailto:redhat-list-bounces@xxxxxxxxxx] On Behalf Of Pete Nesbitt > > > Sent: Tuesday, April 27, 2004 6:35 PM > > > To: frank@xxxxxxxxxxx; General Red Hat Linux discussion list > > > Subject: [redhat] Re: Remote Desktop/Firewall > > > > > > On April 27, 2004 06:06 pm, Frank Reichenbacher wrote: > > > > I have pmfirewall (www.pointman.org) running on my RH 7.0 > > > > > > server/LAN > > > > > > > Router on a home office setup. It is a simple but effective > > > > > > ipchains > > > > > > > firewall script. > > > > > > > > I need to use my WinXP desktop on the inside of the home > > > > > > firewall to > > > > > > > communicate with my office WinXP, which is inside a > > > > > > firewalled router > > > > > > > on a Win2K LAN. The home side outernet IP is 66.93.153.62, > > > > > > innernet IP > > > > > > > 192.168.1.2. The office side outernet IP is 64.232.168.34, the > > > > innernet IP is 192.168.1.103. > > > > > > > > I didn't see in the script a place that closes off the RDP > > > > > > port 3389 > > > > > > > specifically, so I added the following two rules at the > end of the > > > > script. > > > > > > > > $IPCHAINS -A input -p tcp -s 64.232.168.34 > --source-port 3389 -d > > > > 192.168.1.2 --destination-port 3389 -j ACCEPT > > > > > > > > I've also tried combinations of ports 0:65535, 3389 and > there is > > > > no difference. The logs show that the firewall is > denying a return > > > > of bits from the 64.232.168.34 IP on port 65535. I am > contacting > > > > the remote network, but it is blocked on my end from > returning any > > > > packets. > > > > > > > > When I run ipchains from the prompt, I see that port 3389 > > > > > > is open to > > > > > > > 64.232.168.34, I don't seem to see anything that > appears to deny > > > > it afterwards. > > > > > > > > Frank > > > > > > Frank, > > > Do you have input, forward and output chains for that port? (as I > > > recall, ipchains needs all 3 to make the path thru the firewall) > > > > > > Your routers/gateways must be doing NAT on the outside > (presuming an > > > internet connection), so it is not a destination of > 192.168.1.2 that > > > the input chain > > > needs to allow, it is destination 66.93.153.62 > > > > I'll check on the other stuff. If I allow 66.93.153.62, how > do I then > > get packets to 192.168.1.2? > > > > Frank > > > It's been a while since I used IPchains, but I beleive you > want something > like: > > $IPCHAINS -A input -p tcp -s 64.232.168.34 -sport 3389 -d > 66.93.153.62 -dport > 3389 -j REDIRECT 192.168.1.2 > $IPCHAINS -A forward -p tcp -d 192.168.1.2 -dport 3389 -j > ACCEPT $IPCHAINS -A output -p tcp -d 192.168.1.2 -dport 3389 -j ACCEPT Here's what didn't generate error messages when I restarted the firewall: $IPCHAINS -A input -p tcp -s 64.232.168.34 3389 -d 66.93.153.62 3389 -j REDIR 192.168.1.2 3389 $IPCHAINS -A forward -p tcp -d 192.168.1.2 3389 -j ACCEPT $IPCHAINS -A output -p tcp -d 192.168.1.2 3389 -j ACCEPT (RH barks at REDIRECT) And then this is what shows up in /var/log/messages: May 2 19:35:25 mollynet kernel: Packet log: input DENY eth0 PROTO=47 64.232.168.34:65535 66.93.153.62:65535 L=65 S=0x00 I=52375 F=0x0000 T=54 (#42) It's always port 65535. It occurs to me that the Microsoft RDP is not only using port 3389. I think my connection request is received by the remote machine and then answered, but the firewall isn't allowing the return packets to be received on the local machine. I've tried a dozen configurations of port openings, but I admit that I have no idea of what would be correct, and, of course, none of them work. > > You should have a look at: > http://www.ibiblio.org/pub/Linux/docs/HOWTO/other-formats/html _single/IPCHAINS-HOWTO.html I read this, but I am still too much of a newbie to be aable to apply it to my purpose. REDIRECT and REDIR, for example, are barely mentioned. Frank -- Pete Nesbitt, rhce -- redhat-list mailing list unsubscribe mailto:redhat-list-request@xxxxxxxxxx?subject=unsubscribe https://www.redhat.com/mailman/listinfo/redhat-list -- redhat-list mailing list unsubscribe mailto:redhat-list-request@xxxxxxxxxx?subject=unsubscribe https://www.redhat.com/mailman/listinfo/redhat-list
