1FIREWALLD.POLICIES(5) firewalld.policies FIREWALLD.POLICIES(5)
2
3
4
6 firewalld.policies - firewalld policies
7
9 What is a policy?
10 A policy applies a set of rules to traffic flowing between between
11 zones (see zones (see firewalld.zones(5)). The policy affects traffic
12 in a stateful unidirectional manner, e.g. zoneA to zoneB. This allows
13 asynchronous filtering policies.
14
15 A policy's relationship to zones is defined by assigning a set of
16 ingress zones and a set of egress zones. For example, if the set of
17 ingress zones contains "public" and the set of egress zones contains
18 "internal" then the policy will affect all traffic flowing from the
19 "public" zone to the "internal" zone. However, since policies are
20 unidirectional it will not apply to traffic flowing from "internal" to
21 "public". Note that the ingress set and egress set can contain multiple
22 zones.
23
24 Active Policies
25 Policies only become active if all of the following are true.
26
27 • The ingress zones list contain at least one regular zone or a
28 single symbolic zone.
29
30 • The egress zones list contain at least one regular zone or a single
31 symbolic zone.
32
33 • For non symbolic zones, the zone must be active. That is, it must
34 have interfaces or sources assigned to it.
35
36 If the policy is not active then the policy has no effect.
37
38 Symbolic Zones
39 Regular zones are not enough to express every form of packet filtering.
40 For example there is no zone to represent traffic flowing to or from
41 the host running firewalld. As such, there are some symbolic zones to
42 fill these gaps. However, symbolic zones are unique in that they're the
43 only zone allowed in the ingress or egress zone sets. For example, you
44 cannot use "public" and "HOST" in the ingress zones.
45
46 Symbolic zones:
47
48 1. HOST
49
50 This symbolic zone is for traffic flowing to or from the host
51 running firewalld. This corresponds to netfilter
52 (iptables/nftables) chains INPUT and OUTPUT.
53
54 • If used in the egress zones list it will apply to traffic on
55 the INPUT chain.
56
57 • If used in the ingress zones list it will apply to traffic on
58 the OUTPUT chain.
59
60 2. ANY
61
62 This symbolic zone behaves like a wildcard for the ingress and
63 egress zones. With the exception that it does not include "HOST".
64 It's useful if you want a policy to apply to every zone.
65
66 • If used in the ingress zones list it will apply for traffic
67 originating from any zone.
68
69 • If used in the egress zones list it will apply for traffic
70 destined to any zone.
71
72 Predefined Policies
73 firewalld ships with some predefined policies. These may or may not be
74 active by default. For details see the description of each policy.
75
76 • allow-host-ipv6
77
78 Similarity to Zones
79 Policies are similar to zones in that they are an attachment point for
80 firewalld's primitives: services, ports, forward ports, etc. This is
81 not a coincidence. Policies are a generalization of how zones have
82 traditionally achieved filtering. In fact, in modern firewalld zones
83 are internally implemented as a set of policies.
84
85 The main difference between policies and zones is that policies allow
86 filtering in all directions: input, output, and forwarding. With a
87 couple of exceptions zones only allow input filtering which is
88 sufficient for an end station firewalling. However, for network level
89 filtering or filtering on behalf of virtual machines and containers
90 something more flexible, i.e. policies, are needed.
91
93 firewall-applet(1), firewalld(1), firewall-cmd(1), firewall-config(1),
94 firewalld.conf(5), firewalld.direct(5), firewalld.dbus(5),
95 firewalld.icmptype(5), firewalld.lockdown-whitelist(5), firewall-
96 offline-cmd(1), firewalld.richlanguage(5), firewalld.service(5),
97 firewalld.zone(5), firewalld.zones(5), firewalld.policy(5),
98 firewalld.policies(5), firewalld.ipset(5), firewalld.helper(5)
99
101 firewalld home page:
102 http://firewalld.org
103
104 More documentation with examples:
105 http://fedoraproject.org/wiki/FirewallD
106
108 Thomas Woerner <twoerner@redhat.com>
109 Developer
110
111 Jiri Popelka <jpopelka@redhat.com>
112 Developer
113
114 Eric Garver <eric@garver.life>
115 Developer
116
117
118
119firewalld 1.3.4 FIREWALLD.POLICIES(5)