Module chain 

Firewall chain and table management

Implements the netfilter-style chain architecture with five hook points (PreRouting, Input, Forward, Output, PostRouting), three table types (Filter, Nat, Mangle), and a packet processing engine that evaluates rules in priority order and returns a verdict.

Structs

Chain

A chain of firewall rules evaluated in order

FirewallEngine

The main firewall engine that manages tables and processes packets

FirewallTable

A firewall table containing chains for a specific purpose

Enums

ChainPolicy

Default policy for a chain when no rules match

ChainType

Type of firewall table

HookPoint

Netfilter-style hook points in the packet processing path

Verdict

Result of processing a packet through the firewall

Functions

init

Initialize the firewall chain subsystem

with_engine

Access the global firewall engine