Gentoo Archives: gentoo-security

From: Mickey Mullin <mickey@×××××××××.us>
To: gentoo-security@l.g.o
Subject: Re: [gentoo-security] firewall suggestions?
Date: Thu, 08 Jan 2004 03:29:11
Message-Id: 3FFCCE10.40605@dreamwolf.us
In Reply to: Re: [gentoo-security] firewall suggestions? by Mark Hurst
1 Mark Hurst wrote:
2 > It's much better to have a firewall than just have ports not open. Even
3 > though a port is not open it can reveal the presence of your machine by
4 > the manner in which the IP stack responds to a connection attempt. Using a
5 > firewall you can drop those packets, making all your closed ports
6 > invisible.
7
8 If by "firewall," you mean an application(Process ID?)-specific Internet
9 security tool, then you may well have identified an as-yet unfulfilled
10 need. If you only mean to imply greater security in that connection
11 attempts to closed ports appear invisible, then iptables aready does that.
12
13 In "closing" ports, one has the option - nay one is recommended - to use
14 the "DROP" target which has the desired effect of which you speak.
15 (Unwanted packets are simply and silently dropped upon the proverbial
16 floor.) There are, of course, cases where using, say, "REJECT" may be
17 prefered - most notably if one is using one's Linux box to do some true
18 grit routing (as when using multiple Internet service providers). In
19 those cases, if a neighboring router is trying to pass packets *through*
20 one's area, one wants to let one's neighbor know as soon as possible
21 that it should look elsewhere.
22
23 dreamwolf
24
25
26 --
27 gentoo-security@g.o mailing list

Replies

Subject Author
Re: [gentoo-security] firewall suggestions? "Thomas T. Veldhouse" <veldy@×××××.net>