ipchains

Linux IP Firewalling Chains, normally called ipchains, is <a href="/facts/Free_software/IaoVtJXn">free software</a> to control the <a href="/facts/Packet_filter/Et2RkJaU">packet filter</a> or <a href="/facts/Firewall_(networking)/Et2RkJaU">firewall</a> capabilities in the 2.2 series of <a href="/facts/Linux_kernel/dlkduHuA">Linux kernels</a>. It superseded <a href="/facts/Ipfirewall/dB0nV6we">ipfirewall</a> (managed by ipfwadm command), but was replaced by <a href="/facts/Iptables/MHGwCkwR">iptables</a> in the 2.4 series. Unlike iptables, ipchains is <a href="/facts/Stateful_firewall/eCIseahN">stateless</a>.
It is a rewrite of Linux's previous <a href="/facts/IPv4/bnQ5MEqm">IPv4</a> <a href="/facts/Firewall_(networking)/Et2RkJaU">firewall</a>, <a href="/facts/Ipfirewall/dB0nV6we">ipfirewall</a>. This newer ipchains was required to manage the <a href="/facts/Packet_filter/Et2RkJaU">packet filter</a> in <a href="/facts/Linux_kernel/dlkduHuA">Linux kernels</a> starting with version 2.1.102 (which was a 2.2 development release). Patches are also available to add ipchains to 2.0 and earlier 2.1 series kernels. Improvements include larger maxima for packet <a href="/facts/Counting/DsRhH9RT">counting</a>, filtering for <a href="/facts/IP_fragmentation/efmuF7f2">fragmented packets</a> and a wider range of <a href="/facts/Protocol_(computing)/5uady7cB">protocols</a>, and the ability to match packets based on the inverse of a rule.
The ipchains suite also included some shell scripts for easier maintenance and to emulate the behavior of the old ipfwadm command.
The ipchains software was superseded by the <a href="/facts/Iptables/MHGwCkwR">iptables</a> system in <a href="/facts/Linux_kernel/dlkduHuA">Linux kernel</a> 2.4 and above, which was in turn superseded by the <a href="/facts/Nftables/G26b8IvM">nftables</a> system in 2014.

ipchains open-in-new

ipchains