+[[chapter_pve_firewall]]
ifdef::manvolnum[]
-PVE({manvolnum})
-================
-include::attributes.txt[]
+pve-firewall(8)
+===============
+:pve-toplevel:
NAME
----
pve-firewall - PVE Firewall Daemon
-SYNOPSYS
+SYNOPSIS
--------
include::pve-firewall.8-synopsis.adoc[]
DESCRIPTION
-----------
endif::manvolnum[]
-
ifndef::manvolnum[]
{pve} Firewall
==============
-include::attributes.txt[]
+:pve-toplevel:
endif::manvolnum[]
+ifdef::wiki[]
+:title: Firewall
+endif::wiki[]
-Proxmox VE Firewall provides an easy way to protect your IT
+{pve} Firewall provides an easy way to protect your IT
infrastructure. You can setup firewall rules for all hosts
inside a cluster, or define rules for virtual machines and
containers. Features like firewall macros, security groups, IP sets
and aliases help to make that task easier.
While all configuration is stored on the cluster file system, the
-`iptables`-based firewall runs on each cluster node, and thus provides
+`iptables`-based firewall service runs on each cluster node, and thus provides
full isolation between virtual machines. The distributed nature of
this system also provides much higher bandwidth than a central
firewall solution.
cluster nodes, and the `pve-firewall` service updates the underlying
`iptables` rules automatically on changes.
-You can configure anything using the GUI (i.e. Datacenter -> Firewall,
-or on a Node -> Firewall), or you can edit the configuration files
+You can configure anything using the GUI (i.e. *Datacenter* -> *Firewall*,
+or on a *Node* -> *Firewall*), or you can edit the configuration files
directly using your preferred editor.
-Firewall configuration files contains sections of key-value
+Firewall configuration files contain sections of key-value
pairs. Lines beginning with a `#` and blank lines are considered
-comments. Sections starts with a header line containing the section
+comments. Sections start with a header line containing the section
name enclosed in `[` and `]`.
+[[pve_firewall_cluster_wide_setup]]
Cluster Wide Setup
~~~~~~~~~~~~~~~~~~
firewall rules to access the GUI from remote.
+[[pve_firewall_host_specific_configuration]]
Host Specific Configuration
~~~~~~~~~~~~~~~~~~~~~~~~~~~
This sections contains host specific firewall rules.
-
+[[pve_firewall_vm_container_configuration]]
VM/Container Configuration
~~~~~~~~~~~~~~~~~~~~~~~~~~
can selectively enable the firewall for each interface. This is
required in addition to the general firewall `enable` option.
-The firewall requires a special network device setup, so you need to
-restart the VM/container after enabling the firewall on a network
-interface.
-
Firewall Rules
--------------
IN SSH(ACCEPT) -i net0
IN SSH(ACCEPT) -i net0 # a comment
IN SSH(ACCEPT) -i net0 -source 192.168.2.192 # only allow SSH from 192.168.2.192
-IN SSH(ACCEPT) -i net0 -source 10.0.0.1-10.0.0.10 # accept SSH for ip range
-IN SSH(ACCEPT) -i net0 -source 10.0.0.1,10.0.0.2,10.0.0.3 #accept ssh for ip list
+IN SSH(ACCEPT) -i net0 -source 10.0.0.1-10.0.0.10 # accept SSH for IP range
+IN SSH(ACCEPT) -i net0 -source 10.0.0.1,10.0.0.2,10.0.0.3 #accept ssh for IP list
IN SSH(ACCEPT) -i net0 -source +mynetgroup # accept ssh for ipset mynetgroup
IN SSH(ACCEPT) -i net0 -source myserveralias #accept ssh for alias myserveralias
----
+[[pve_firewall_security_groups]]
Security Groups
---------------
GROUP webserver
----
-
+[[pve_firewall_ip_aliases]]
IP Aliases
----------
----
# /etc/pve/firewall/cluster.fw
[ALIASES]
-local_network 1.2.3.4 # use the single ip address
+local_network 1.2.3.4 # use the single IP address
----
-
+[[pve_firewall_ip_sets]]
IP Sets
-------
----
-[[ipfilter-section]]
+[[pve_firewall_ipfilter_section]]
Standard IP set `ipfilter-net*`
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
be dropped.
For containers with configured IP addresses these sets, if they exist (or are
-activated via the general `IP Filter` option in the VM's firewall's 'options'
+activated via the general `IP Filter` option in the VM's firewall's *options*
tab), implicitly contain the associated IP addresses.
For both virtual machines and containers they also implicitly contain the
# iptables-save
+[[pve_firewall_default_rules]]
+Default firewall rules
+----------------------
+
+The following traffic is filtered by the default firewall configuration:
+
+Datacenter incomming/outgoing DROP/REJECT
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+If the input/output policy for the firewall is set to DROP/REJECT, the following
+traffic is still allowed for the host:
+
+* traffic over the loopback interface
+* already established connections
+* traffic using the igmp protocol
+* tcp traffic from management hosts to port 8006 in order to allow access to
+the web interface
+* tcp traffic from management hosts to the port range 5900 to 5999 allowing
+traffic for the VNC web console
+* tcp traffic from management hosts to port 3128 for connections to the SPICE
+proxy
+* tcp traffic from management hosts to port 22 to allow ssh access
+* udp traffic in the cluster network to port 5404 and 5405 for corosync
+* udp multicast traffic in the cluster network
+* icmp traffic type 3,4 or 11
+
+The following traffic is dropped, but not logged even with logging enabled:
+
+* tcp connections with invalid connection state
+* Broad-, multi- and anycast traffic not related to corosync
+* tcp traffic to port 43
+* udp traffic to ports 135 and 445
+* udp traffic to the port range 137 to 139
+* udp traffic form source port 137 to port range 1024 to 65535
+* udp traffic to port 1900
+* tcp traffic to port 135, 139 and 445
+* udp traffic originating from source port 53
+
+The rest of the traffic is dropped/rejected and logged.
+This may vary depending on the additional options enabled in
+*Firewall* -> *Options*, such as NDP, SMURFS and TCP flag filtering.
+
+Please inspect the output of
+
+ # iptables-save
+
+to see the firewall chains and rules active on your system.
+
+VM/CT incomming/outgoing DROP/REJECT
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+This drops/rejects all the traffic to the VMs, with some exceptions for DHCP, NDP,
+Router Advertisement, MAC and IP filtering depending on the set configuration.
+The same rules for dropping/rejecting packets are inherited from the datacenter,
+while the exceptions for accepted incomming/outgoing traffic of the host do not
+apply.
+
+Again, please inspect the output of
+
+ # iptables-save
+
+to see in detail the firewall chains and rules active for the VMs/CTs.
+
+Logging of firewall rules
+-------------------------
+
+By default, all logging of traffic filtered by the firewall rules is disabled.
+To enable logging, the `loglevel` for incommig and/or outgoing traffic has to be
+set in *Firewall* -> *Options*. This can be done for the host as well as for the
+VM/CT firewall individually. By this, logging of {PVE}'s standard firewall rules
+is enabled and the output can be observed in *Firewall* -> *Log*.
+Further, only some dropped or rejected packets are logged for the standard rules
+(see xref:pve_firewall_default_rules[default firewall rules]).
+
+`loglevel` does not affect how much of the filtered traffic is logged. It
+changes a `LOGID` appended as prefix to the log output for easier filtering and
+post-processing.
+
+`loglevel` is one of the following flags:
+
+[[pve_firewall_log_levels]]
+[width="25%", options="header"]
+|===================
+| loglevel | LOGID
+| nolog | no log
+| emerg | 0
+| alert | 1
+| crit | 2
+| err | 3
+| warning | 4
+| notice | 5
+| info | 6
+| debug | 7
+|===================
+
+A typical firewall log output looks like this:
+
+----
+VMID LOGID CHAIN TIMESTAMP POLICY: PACKET_DETAILS
+----
+
+In case of the host firewall, `VMID` is equal to 0.
+
+
+Logging of user defined firewall rules
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+In order to log packets filtered by user-defined firewall rules, it is possible
+to set a log-level parameter for each rule individually.
+This allows to log in a fine grained manner and independent of the log-level
+defined for the standard rules in *Firewall* -> *Options*.
+
+While the `loglevel` for each individual rule can be defined or changed easily
+in the WebUI during creation or modification of the rule, it is possible to set
+this also via the corresponding `pvesh` API calls.
+
+Further, the log-level can also be set via the firewall configuration file by
+appending a `-log <loglevel>` to the selected rule (see
+xref:pve_firewall_log_levels[possible log-levels]).
+
+For example, the following two are ident:
+
+----
+IN REJECT -p icmp -log nolog
+IN REJECT -p icmp
+----
+
+whereas
+
+----
+IN REJECT -p icmp -log debug
+----
+
+produces a log output flagged with the `debug` level.
+
Tips and Tricks
---------------
----
-Avoiding `link-local` Addresses on `tap` and `veth` Devices
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-With IPv6 enabled by default every interface gets a MAC-derived link local
-address. However, most devices on a typical {pve} setup are connected to a
-bridge and so the bridge is the only interface which really needs one.
-
-To disable a link local address on an interface you can set the interface's
-`disable_ipv6` sysconf variable. Despite the name, this does not prevent IPv6
-traffic from passing through the interface when routing or bridging, so the
-only noticeable effect will be the removal of the link local address.
-
-The easiest method of achieving this setting for all newly started VMs is to
-set it for the `default` interface configuration and enabling it explicitly on
-the interfaces which need it. This is also the case for other settings such as
-`forwarding`, `accept_ra` or `autoconf`.
-
-Here's a possible setup:
-----
-# /etc/sysconf.d/90-ipv6.conf
-
-net.ipv6.conf.default.forwarding = 0
-net.ipv6.conf.default.proxy_ndp = 0
-net.ipv6.conf.default.autoconf = 0
-net.ipv6.conf.default.disable_ipv6 = 1
-net.ipv6.conf.default.accept_ra = 0
-
-net.ipv6.conf.lo.disable_ipv6 = 0
-----
-
-----
-# /etc/network/interfaces
-(...)
-# Dual stack:
-iface vmbr0 inet static
- address 1.2.3.4
- netmask 255.255.255.128
- gateway 1.2.3.5
-iface vmbr0 inet6 static
- address fc00::31
- netmask 16
- gateway fc00::1
- accept_ra 0
- pre-up echo 0 > /proc/sys/net/ipv6/conf/$IFACE/disable_ipv6
-
-# With IPv6-only 'pre-up' is too early and 'up' is too late.
-# Work around this by creating the bridge manually
-iface vmbr1 inet manual
- pre-up ip link add $IFACE type bridge
- up echo 0 > /proc/sys/net/ipv6/conf/$IFACE/disable_ipv6
-iface vmbr1 inet6 static
- address fc00:b:3::1
- netmask 96
- bridge_ports none
- bridge_stp off
- bridge_fd 0
- bridge_vlan_aware yes
- accept_ra 0
-(...)
-----
-
-
Notes on IPv6
-------------
level to allow neighbor discovery (NDP) packets to be sent and received.
Beside neighbor discovery NDP is also used for a couple of other things, like
-autoconfiguration and advertising routers.
+auto-configuration and advertising routers.
By default VMs are allowed to send out router solicitation messages (to query
for a router), and to receive router advertisement packets. This allows them to
(`ipfilter: 1`) option which can be enabled which has the same effect as adding
an `ipfilter-net*` ipset for each of the VM's network interfaces containing the
corresponding link local addresses. (See the
-<<ipfilter-section,Standard IP set `ipfilter-net*`>> section for details.)
+<<pve_firewall_ipfilter_section,Standard IP set `ipfilter-net*`>> section for details.)
-Ports used by Proxmox VE
-------------------------
+Ports used by {pve}
+-------------------
* Web interface: 8006
* VNC Web console: 5900-5999
projects / pve-docs.git / blobdiff