I'm setting up public access to a remote/internal server, on a specific port,
over a private VPN.
Topology is:
Net
|
| eth0 (IP = AA.AA.AA.AA)
"Public Server" (Shorewall)
| vpn0 <-> "Private Edge:vpn0"
|
| eth0 (IP = BB.BB.BB.BB)
"Private Edge" (Shorewall)
| vpn0 <-> "Public Server:vpn0"
| eth1 (IP = 10.10.10.1)
|
| eth0 (IP = 10.10.10.99)
"Private Server"
SERVER APP LISTENER @: 10.10.10.99:12345
Goal is:
external traffic, from XX.XX.XX.XX, to AA.AA.AA.AA:12345 flows to
10.10.10.99:12345,
&,
responses route back from 10.10.10.99:12345 to originating XX.XX.XX.XX
Configs include:
Shorewall @ "Public Server":
/rules
ACCEPT net $FW:AA.AA.AA.AA tcp 12345
DNAT net vpn:10.10.10.99 tcp 12345 -
AA.AA.AA.AA
&,
Shorewall @ "Private Edge"
/rules
ACCEPT vpn lan:10.10.10.99 tcp 12345
DNAT vpn lan:10.10.10.99 tcp 12345 -
10.10.10.99
With that^^, access from the 'net DOES make it to the LISTENER.
Inbound,
@ "Private Edge"
tcpdump -n -i vpn0 port 12345
IP XX.XX.XX.XX.21959 > 10.10.10.99.12345: Flags [S], seq
448812557, win 65535, options [mss 1224,sackOK,TS val 14593152 ecr 0,nop,wscale
8], length 0
@ "Private Server":LISTENER
tcpdump -n -i eth0 port 12345
16:12:25.703719 IP XX.XX.XX.XX.21959 > 10.10.10.99.12345: Flags
[S], seq 1958940743, win 65535, options [mss 1224,sackOK,TS val 14699632 ecr
0,nop,wscale 8], length 0
Outbound, the reply *is* generated
@ "Private Server":LISTENER
tcpdump -n -i eth0 port 12345
16:12:25.703808 IP 10.10.10.99.12345 > XX.XX.XX.XX.21959: Flags
[S.], seq 891560507, ack 2837133672, win 65160, options [mss 1460,sackOK,TS val
3577618011 ecr 14699376,nop,wscale 7], length 0
but FAILs to route back over the VPN link; I don't see the traffic return via
intfc = vpn0.
it's instead appearing on the EXTERNAL interface
@ "Private Edge"
tcpdump -n -i eth0 src port 12345
^^^
16:12:26.822716 IP 10.10.10.99.12345 > XX.XX.XX.XX.21959: Flags
[S.], seq 891560507, ack 2837133672, win 65160, options [mss 1460,sackOK,TS val
3577620033 ecr 14699376,nop,wscale 7], length 0
Where does that mis-routeback need to get fixed? so the traffic return is via
"Private Edge" *vpn0*, NOT *eth0*?
Do I need to mod my DNAT?
Add a SNAT?
Or, add static routes?
_______________________________________________
Shorewall-users mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/shorewall-users
