Iptables Operations

The iptables modules handles iptables rules

Facts used in these operations: iptables.Ip6tablesChains, iptables.Ip6tablesRules, iptables.IptablesChains, iptables.IptablesRules.

iptables.chain

Add/remove/update iptables chains.

iptables.chain(chain, present=True, table="filter", policy=None, version=4)

• chain: the name of the chain
• present: whether the chain should exist
• table: the iptables table this chain should belong to
• policy: the policy this table should have
• version: whether to target iptables or ip6tables

Policy:

These can only be applied to system chains (FORWARD, INPUT, OUTPUT, etc).

iptables.rule

Add/remove iptables rules.

iptables.rule(
    chain, jump, present=True, table="filter", append=True, version=4, protocol=None,
    not_protocol=None, source=None, not_source=None, destination=None, not_destination=None,
    in_interface=None, not_in_interface=None, out_interface=None, not_out_interface=None,
    to_destination=None, to_source=None, to_ports=None, log_prefix=None,
    destination_port=None, source_port=None, extras="",
)

• chain: the chain this rule should live in
• jump: the target of the rule
• table: the iptables table this rule should belong to
• append: whether to append or insert the rule (if not present)
• version: whether to target iptables or ip6tables

Iptables args:

• protocol/not_protocol: filter by protocol (tcp or udp)
• source/not_source: filter by source IPs
• destination/not_destination: filter by destination IPs
• in_interface/not_in_interface: filter by incoming interface
• out_interface/not_out_interface: filter by outgoing interface
• to_destination: where to route to when jump=DNAT
• to_source: where to route to when jump=SNAT
• to_ports: where to route to when jump=REDIRECT
• log_prefix: prefix for the log of this rule when jump=LOG

Extras:

• extras: a place to define iptables extension arguments (eg –limit, –physdev)
• destination_port: destination port (requires protocol)
• source_port: source port (requires protocol)

Examples:

iptables.rule(
    name="Block SSH traffic",
    chain="INPUT",
    jump="DROP",
    destination_port=22,
)

iptables.rule(
    name="NAT traffic on from 8.8.8.8:53 to 8.8.4.4:8080",
    chain="PREROUTING",
    jump="DNAT",
    table="nat",
    source="8.8.8.8",
    destination_port=53,
    to_destination="8.8.4.4:8080",
)