Firewall Wizards mailing list archives
Blocking ICMP with ipchains
From: wwebb () adni net
Date: Tue, 11 Jan 2000 19:18:59 -0500
I've heard that it is not wise to block all ICMP operations. Such being the case, which of these ICMP operations are safe to block without causing serious problems: echo-reply (pong) destination-unreachable network-unreachable host-unreachable protocol-unreachable port-unreachable fragmentation-needed source-route-failed network-unknown host-unknown network-prohibited host-prohibited TOS-network-unreachable TOS-host-unreachable communication-prohibited host-precedence-violation precedence-cutoff source-quench redirect network-redirect host-redirect TOS-network-redirect TOS-host-redirect echo-request (ping) router-advertisement router-solicitation time-exceeded (ttl-exceeded) ttl-zero-during-transit ttl-zero-during-reassembly parameter-problem ip-header-bad required-option-missing timestamp-request timestamp-reply address-mask-request address-mask-reply Thanks for any assistance.
Current thread:
- Blocking ICMP with ipchains wwebb (Jan 13)
- Re: Blocking ICMP with ipchains Mikael Olsson (Jan 15)
- Re: Blocking ICMP with ipchains Carric Dooley (Jan 16)
- <Possible follow-ups>
- RE: Blocking ICMP with ipchains peter . schawacker (Jan 16)
- RE: Blocking ICMP with ipchains Ryan Russell (Jan 17)
- Re: Blocking ICMP with ipchains Steven M. Bellovin (Jan 17)
- RE: Blocking ICMP with ipchains Richard . Smyth (Jan 17)
- RE: Blocking ICMP with ipchains Staggs, Michael (Jan 18)