auto-generate firewall rule options
[pve-docs.git] / pve-firewall.adoc
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1ifdef::manvolnum[]
2PVE({manvolnum})
3================
38fd0958 4include::attributes.txt[]
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5
6NAME
7----
8
9pve-firewall - The PVE Firewall Daemon
10
11
12SYNOPSYS
13--------
14
5f34196d 15include::pve-firewall.8-synopsis.adoc[]
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16
17
18DESCRIPTION
19-----------
20endif::manvolnum[]
21
22ifndef::manvolnum[]
23{pve} Firewall
24==============
38fd0958 25include::attributes.txt[]
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26endif::manvolnum[]
27
28// Copied from pve wiki: Revision as of 08:45, 9 November 2015
29
30Proxmox VE Firewall provides an easy way to protect your IT
31infrastructure. You can easily setup firewall rules for all hosts
32inside a cluster, or define rules for virtual machines and
33containers. Features like firewall macros, security groups, IP sets
34and aliases help making that task easier.
35
36While all configuration is stored on the cluster file system, the
37iptables based firewall runs on each cluster node, and thus provides
38full isolation between virtual machines. The distributed nature of
39this system also provides much higher bandwidth than a central
40firewall solution.
41
42NOTE: If you enable the firewall, all traffic is blocked by default,
43except WebGUI(8006) and ssh(22) from your local network.
44
45
46Zones
47-----
48
49The Proxmox VE firewall groups the network into the following logical zones:
50
51Host::
52
53Traffic from/to a cluster node
54
55VM::
56
57Traffic from/to a specific VM
58
59For each zone, you can define firewall rules for incoming and/or
60outgoing traffic.
61
62
63Ports used by Proxmox VE
64------------------------
65
66* Web interface: 8006
67* VNC Web console: 5900-5999
68* SPICE proxy: 3128
69* sshd (used for cluster actions): 22
70* rpcbind: 111
71* corosync multicast (if you run a cluster): 5404, 5405 UDP
72
73
74Configuration
75-------------
76
77All firewall related configuration is stored on the proxmox cluster
78file system. So those files are automatically distributed to all
79cluster nodes, and the 'pve-firewall' service updates the underlying
80iptables rules automatically on any change. Any configuration can be
81done using the GUI (i.e. Datacenter -> Firewall -> Options tab (tabs
82at the bottom of the page), or on a Node -> Firewall), so the
83following configuration file snippets are just for completeness.
84
85Cluster wide configuration is stored at:
86
87 /etc/pve/firewall/cluster.fw
88
89The firewall is completely disabled by default, so you need to set the
90enable option here:
91
92----
93[OPTIONS]
94# enable firewall (cluster wide setting, default is disabled)
95enable: 1
96----
97
98The cluster wide configuration can contain the following data:
99
100* IP set definitions
101* Alias definitions
102* Security group definitions
103* Cluster wide firewall rules for all nodes
104
105VM firewall configuration is read from:
106
107 /etc/pve/firewall/<VMID>.fw
108
109and contains the following data:
110
111* IP set definitions
112* Alias definitions
113* Firewall rules for this VM
114* VM specific options
115
116And finally, any host related configuration is read from:
117
118 /etc/pve/nodes/<nodename>/host.fw
119
120This is useful if you want to overwrite rules from 'cluster.fw'
121config. You can also increase log verbosity, and set netfilter related
122options.
123
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124Enabling the Firewall for VMs and Containers
125~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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127You need to enable the firewall on the virtual network interface configuration
128in addition to the general 'Enable Firewall' option in the 'Options' tab.
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129
130Firewall Rules
131~~~~~~~~~~~~~~
132
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133Firewall rules consists of a direction (`IN` or `OUT`) and an
134action (`ACCEPT`, `DENY`, `REJECT`). You can also specify a macro
135name. Macros contain predifined sets of rules and options. Rules can be disabled by prefixing them with '|'.
c7eda5e6 136
696fb448 137.Firewall rules syntax
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138----
139[RULES]
140
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141DIRECTION ACTION [OPTIONS]
142|DIRECTION ACTION [OPTIONS] # disabled rule
c7eda5e6 143
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144DIRECTION MACRO(ACTION) [OPTIONS] # use predefined macro
145----
146
147The following options can be used to refine rule matches.
148
149include::pve-firewall-rules-opts.adoc[]
150
151Here are some examples:
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153----
154[RULES]
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155IN SSH(ACCEPT) -i net0
156IN SSH(ACCEPT) -i net0 # a comment
696fb448 157IN SSH(ACCEPT) -i net0 -source 192.168.2.192 # only allow SSH from 192.168.2.192
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158IN SSH(ACCEPT) -i net0 -source 10.0.0.1-10.0.0.10 # accept SSH for ip range
159IN SSH(ACCEPT) -i net0 -source 10.0.0.1,10.0.0.2,10.0.0.3 #accept ssh for ip list
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160IN SSH(ACCEPT) -i net0 -source +mynetgroup # accept ssh for ipset mynetgroup
161IN SSH(ACCEPT) -i net0 -source myserveralias #accept ssh for alias myserveralias
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162
163|IN SSH(ACCEPT) -i net0 # disabled rule
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164
165IN DROP # drop all incoming packages
166OUT ACCEPT # accept all outgoing packages
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167----
168
169Security Groups
170~~~~~~~~~~~~~~~
171
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172A security group is a collection of rules, defined at cluster level, which
173can be used in all VMs' rules. For example you can define a group named
174`webserver` with rules to open the http and https ports.
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175
176----
177# /etc/pve/firewall/cluster.fw
178
179[group webserver]
180IN ACCEPT -p tcp -dport 80
181IN ACCEPT -p tcp -dport 443
182----
183
58b16f71 184Then, you can add this group to a VM's firewall
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185
186----
187# /etc/pve/firewall/<VMID>.fw
188
189[RULES]
190GROUP webserver
191----
192
193
194IP Aliases
195~~~~~~~~~~
196
58b16f71 197IP Aliases allow you to associate IP addresses of networks with a
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198name. You can then refer to those names:
199
200* inside IP set definitions
201* in `source` and `dest` properties of firewall rules
202
203Standard IP alias `local_network`
204^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
205
206This alias is automatically defined. Please use the following command
207to see assigned values:
208
209----
210# pve-firewall localnet
211local hostname: example
212local IP address: 192.168.2.100
213network auto detect: 192.168.0.0/20
214using detected local_network: 192.168.0.0/20
215----
216
217The firewall automatically sets up rules to allow everything needed
58b16f71 218for cluster communication (corosync, API, SSH) using this alias.
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219
220The user can overwrite these values in the cluster.fw alias
221section. If you use a single host on a public network, it is better to
222explicitly assign the local IP address
223
224----
225# /etc/pve/firewall/cluster.fw
226[ALIASES]
227local_network 1.2.3.4 # use the single ip address
228----
229
230IP Sets
231~~~~~~~
232
233IP sets can be used to define groups of networks and hosts. You can
58b16f71 234refer to them with `+name` in the firewall rules' `source` and `dest`
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235properties.
236
237The following example allows HTTP traffic from the `management` IP
238set.
239
240 IN HTTP(ACCEPT) -source +management
241
242Standard IP set `management`
243^^^^^^^^^^^^^^^^^^^^^^^^^^^^
244
245This IP set applies only to host firewalls (not VM firewalls). Those
246ips are allowed to do normal management tasks (PVE GUI, VNC, SPICE,
247SSH).
248
249The local cluster network is automatically added to this IP set (alias
250`cluster_network`), to enable inter-host cluster
251communication. (multicast,ssh,...)
252
253----
254# /etc/pve/firewall/cluster.fw
255
256[IPSET management]
257192.168.2.10
258192.168.2.10/24
259----
260
261Standard IP set 'blacklist'
262^^^^^^^^^^^^^^^^^^^^^^^^^^^
263
58b16f71 264Traffic from these ips is dropped by every host's and VM's firewall.
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265
266----
267# /etc/pve/firewall/cluster.fw
268
269[IPSET blacklist]
27077.240.159.182
271213.87.123.0/24
272----
273
6300d424 274[[ipfilter-section]]
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275Standard IP set 'ipfilter-net*'
276^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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278These filters belong to a VM's network interface and are mainly used to prevent
279IP spoofing. If such a set exists for an interface then any outgoing traffic
280with a source IP not matching its interface's corresponding ipfilter set will
281be dropped.
282
283For containers with configured IP addresses these sets, if they exist (or are
284activated via the general `IP Filter` option in the VM's firewall's 'options'
285tab), implicitly contain the associated IP addresses.
286
287For both virtual machines and containers they also implicitly contain the
288standard MAC-derived IPv6 link-local address in order to allow the neighbor
289discovery protocol to work.
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290
291----
292/etc/pve/firewall/<VMID>.fw
293
294[IPSET ipfilter-net0] # only allow specified IPs on net0
295192.168.2.10
296----
297
298Services and Commands
299~~~~~~~~~~~~~~~~~~~~~
300
301The firewall runs two service daemons on each node:
302
303* pvefw-logger: NFLOG daemon (ulogd replacement).
304* pve-firewall: updates iptables rules
305
306There is also a CLI command named 'pve-firewall', which can be used to
307start and stop the firewall service:
308
309 # pve-firewall start
310 # pve-firewall stop
311
312To get the status use:
313
314 # pve-firewall status
315
316The above command reads and compiles all firewall rules, so you will
317see warnings if your firewall configuration contains any errors.
318
319If you want to see the generated iptables rules you can use:
320
321 # iptables-save
322
323Tips and Tricks
324~~~~~~~~~~~~~~~
325
326How to allow FTP
327^^^^^^^^^^^^^^^^
328
329FTP is an old style protocol which uses port 21 and several other dynamic ports. So you
330need a rule to accept port 21. In addition, you need to load the 'ip_conntrack_ftp' module.
331So please run:
332
333 modprobe ip_conntrack_ftp
334
335and add `ip_conntrack_ftp` to '/etc/modules' (so that it works after a reboot) .
336
337Suricata IPS integration
338^^^^^^^^^^^^^^^^^^^^^^^^
339
340If you want to use the http://suricata-ids.org/[Suricata IPS]
341(Intrusion Prevention System), it's possible.
342
343Packets will be forwarded to the IPS only after the firewall ACCEPTed
344them.
345
346Rejected/Dropped firewall packets don't go to the IPS.
347
348Install suricata on proxmox host:
349
350----
351# apt-get install suricata
352# modprobe nfnetlink_queue
353----
354
355Don't forget to add `nfnetlink_queue` to '/etc/modules' for next reboot.
356
357Then, enable IPS for a specific VM with:
358
359----
360# /etc/pve/firewall/<VMID>.fw
361
362[OPTIONS]
363ips: 1
364ips_queues: 0
365----
366
367`ips_queues` will bind a specific cpu queue for this VM.
368
369Available queues are defined in
370
371----
372# /etc/default/suricata
373NFQUEUE=0
374----
375
376
377ifdef::manvolnum[]
378include::copyright.adoc[]
379endif::manvolnum[]
380
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381Notes on IPv6
382^^^^^^^^^^^^^
383
384The firewall contains a few IPv6 specific options. One thing to note is that
385IPv6 does not use the ARP protocol anymore, and instead uses NDP (Neighbor
386Discovery Protocol) which works on IP level and thus needs IP addresses to
387succeed. For this purpose link-local addresses derived from the interface's MAC
388address are used. By default the 'NDP' option is enabled on both host and VM
389level to allow neighbor discovery (NDP) packets to be sent and received.
390
391Beside neighbor discovery NDP is also used for a couple of other things, like
392autoconfiguration and advertising routers.
393
394By default VMs are allowed to send out router solicitation messages (to query
395for a router), and to receive router advetisement packets. This allows them to
396use stateless auto configuration. On the other hand VMs cannot advertise
397themselves as routers unless the 'Allow Router Advertisement' (`radv: 1`) option
398is set.
399
400As for the link local addresses required for NDP, there's also an 'IP Filter'
401(`ipfilter: 1`) option which can be enabled which has the same effect as adding
402an `ipfilter-net*` ipset for each of the VM's network interfaces containing the
403corresponding link local addresses. (See the
404<<ipfilter-section,Standard IP set 'ipfilter-net*'>> section for details.)
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405
406Avoiding link-local addresses on tap and veth devices
407^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
408
409With IPv6 enabled by default every interface gets a MAC-derived link local
410address. However, most devices on a typical {pve} setup are connected to a
411bridge and so the bridge is the only interface which really needs one.
412
413To disable a link local address on an interface you can set the interface's
414`disable_ipv6` sysconf variable. Despite the name, this does not prevent IPv6
415traffic from passing through the interface when routing or bridging, so the
416only noticeable effect will be the removal of the link local address.
417
418The easiest method of achieving this setting for all newly started VMs is to
419set it for the `default` interface configuration and enabling it explicitly on
420the interfaces which need it. This is also the case for other settings such as
421`forwarding`, `accept_ra` or `autoconf`.
422
423Here's a possible setup:
424----
425# /etc/sysconf.d/90-ipv6.conf
426
427net.ipv6.conf.default.forwarding = 0
428net.ipv6.conf.default.proxy_ndp = 0
429net.ipv6.conf.default.autoconf = 0
430net.ipv6.conf.default.disable_ipv6 = 1
431net.ipv6.conf.default.accept_ra = 0
432
433net.ipv6.conf.lo.disable_ipv6 = 0
434----
435
436----
437# /etc/network/interfaces
438(...)
439iface vmbr0 inet6 static
440 address fc00::31
441 netmask 16
442 gateway fc00::1
443 accept_ra 0
444 pre-up echo 0 > /proc/sys/net/ipv6/conf/$IFACE/disable_ipv6
445(...)
446----