I'm trying to set up some rules using IPtables under Debian (Wheezy) and have been running in to some problems i think.
The policy of INPUT is set to DROP. Does this drop everything based on the rules I put into INPUT or is it like a standard ACL-list in some routers, meaning that everything not matched by the statements (if they are set with ACCEPT) will result in a DROP?
Take this as an example:
Chain INPUT (policy DROP) target prot opt source destination ACCEPT tcp -- anywhere anywhere tcp dpts:ftp-data:ftp
Will these ftp-packets drop or will they be accepted and everything else will drop?
I hope I'm not messing it up to much.