xref: /titanic_51/usr/src/cmd/ipf/examples/ftp-proxy (revision 749f21d359d8fbd020c974a1a5227316221bfc9c)
1How to setup FTP proxying using the built in proxy code.
2========================================================
3
4NOTE: Currently, the built-in FTP proxy is only available for use with NAT
5      (i.e. only if you're already using "map" rules with ipnat).  It does
6      support null-NAT mappings, that is, using the proxy without changing
7      the addresses.
8
9Lets assume your network diagram looks something like this:
10
11
12[host A]
13   |a
14---+-------------+----------
15                 |b
16             [host B]
17                 |c
18---+-------------+----------
19   |d
20[host C]
21
22and IP Filter is running on host B.  If you want to proxy FTP from A to C
23then you would do:
24
25map int-c ipaddr-a/32 -> ip-addr-c-net/32 proxy port ftp ftp/tcp
26
27int-c = name of "interface c"
28ipaddr-a = ip# of interface a
29ipaddr-c-net = another ip# on the C-network (usually not the same as the
30interface).
31
32e.g., if host A was 10.1.1.1, host B had two network interfaces ed0 and vx0
33which had IP#'s 10.1.1.2 and 203.45.67.89 respectively, and host C was
34203.45.67.90, you would do:
35
36map vx0 10.1.1.1/32 -> 203.45.67.91/32 proxy port ftp ftp/tcp
37
38where:
39ipaddr-a = 10.1.1.1
40int-c = vx0
41ipaddr-c-net = 203.45.67.91
42
43The "map" rule for this proxy should precede any other NAT rules you are
44using.
45
46