nanog mailing list archives
Re: Should routers send redirects by default?
From: Jared Mauch <jared () puck nether net>
Date: Fri, 20 Aug 2010 18:29:07 -0400
See below Jared Mauch On Aug 20, 2010, at 6:16 PM, Brandon Ross <bross () pobox com> wrote:
On Fri, 20 Aug 2010, Valdis.Kletnieks () vt edu wrote:Until a PC or something on the network gets pwned, and issues selective forged ICMP redirects to declare itself a router and the appropriate destination for some traffic, which it can then MITM to its heart's content. *Then* you truly have a manure-on-fan situation.I believe the question was along the lines of, "why do I turn this off on my router?" How does turning off ICMP redirects on the router prevent a rouge PC from sending ICMP redirects to it's neighbors? I'm in the same boat here. I know there's a lot of conventional wisdom that says to turn it off, but I'm yet to hear a convincing argument as to why I should bother. Now configuring your hosts to ignore them, that I could understand.
The issue is routers typically do this in software requiring a punt and CPU theft from bgp, ospf etc.
-- Brandon Ross AIM: BrandonNRoss ICQ: 2269442 Skype: brandonross Yahoo: BrandonNRoss
Current thread:
- Re: Should routers send redirects by default?, (continued)
- Re: Should routers send redirects by default? Mikael Abrahamsson (Aug 20)
- Re: Should routers send redirects by default? Jack Bates (Aug 20)
- Re: Should routers send redirects by default? Christopher Morrow (Aug 20)
- Re: Should routers send redirects by default? Mikael Abrahamsson (Aug 20)
- Re: Should routers send redirects by default? Dobbins, Roland (Aug 20)
- Re: Should routers send redirects by default? Butch Evans (Aug 20)
- Re: Should routers send redirects by default? Jared Mauch (Aug 20)
- Re: Should routers send redirects by default? Butch Evans (Aug 20)
- Re: Should routers send redirects by default? Valdis . Kletnieks (Aug 20)
- Re: Should routers send redirects by default? Butch Evans (Aug 20)
- Re: Should routers send redirects by default? Brandon Ross (Aug 20)
- Re: Should routers send redirects by default? Jared Mauch (Aug 20)
- Re: Should routers send redirects by default? Brandon Ross (Aug 20)
- Re: Should routers send redirects by default? Jared Mauch (Aug 20)
- Re: Should routers send redirects by default? Jared Mauch (Aug 20)
- Re: Should routers send redirects by default? Valdis . Kletnieks (Aug 20)
- Re: Should routers send redirects by default? Eric J. Katanich (Aug 20)
- Re: Should routers send redirects by default? Owen DeLong (Aug 20)
- Re: Should routers send redirects by default? Jared Mauch (Aug 20)
- Re: Should routers send redirects by default? James Hess (Aug 25)
- Re: Should routers send redirects by default? Butch Evans (Aug 25)
- Re: Should routers send redirects by default? Christopher Morrow (Aug 20)
- Re: Should routers send redirects by default? Yann GAUTERON (Aug 20)