add auto-generated cluster firewall options
[pve-docs.git] / pve-firewall.adoc
1 ifdef::manvolnum[]
2 PVE({manvolnum})
3 ================
4 include::attributes.txt[]
5
6 NAME
7 ----
8
9 pve-firewall - The PVE Firewall Daemon
10
11
12 SYNOPSYS
13 --------
14
15 include::pve-firewall.8-synopsis.adoc[]
16
17
18 DESCRIPTION
19 -----------
20 endif::manvolnum[]
21
22 ifndef::manvolnum[]
23 {pve} Firewall
24 ==============
25 include::attributes.txt[]
26 endif::manvolnum[]
27
28 // Copied from pve wiki: Revision as of 08:45, 9 November 2015
29
30 Proxmox VE Firewall provides an easy way to protect your IT
31 infrastructure. You can easily setup firewall rules for all hosts
32 inside a cluster, or define rules for virtual machines and
33 containers. Features like firewall macros, security groups, IP sets
34 and aliases help making that task easier.
35
36 While all configuration is stored on the cluster file system, the
37 iptables based firewall runs on each cluster node, and thus provides
38 full isolation between virtual machines. The distributed nature of
39 this system also provides much higher bandwidth than a central
40 firewall solution.
41
42 NOTE: If you enable the firewall, all traffic is blocked by default,
43 except WebGUI(8006) and ssh(22) from your local network.
44
45 The firewall has full support for IPv4 and IPv6. IPv6 support is fully
46 transparent, and we filter traffic for both protocols by default. So
47 there is no need to maintain a different set of rules for IPv6.
48
49
50 Zones
51 -----
52
53 The Proxmox VE firewall groups the network into the following logical zones:
54
55 Host::
56
57 Traffic from/to a cluster node
58
59 VM::
60
61 Traffic from/to a specific VM
62
63 For each zone, you can define firewall rules for incoming and/or
64 outgoing traffic.
65
66
67 Configuration Files
68 -------------------
69
70 All firewall related configuration is stored on the proxmox cluster
71 file system. So those files are automatically distributed to all
72 cluster nodes, and the 'pve-firewall' service updates the underlying
73 iptables rules automatically on changes. Any configuration can be
74 done using the GUI (i.e. Datacenter -> Firewall -> Options tab (tabs
75 at the bottom of the page), or on a Node -> Firewall), so the
76 following configuration file snippets are just for completeness.
77
78 All firewall configuration files contains sections of key-value
79 pairs. Lines beginning with a '#' and blank lines are considered
80 comments. Sections starts with a header line containing the section
81 name enclosed in '[' and ']'.
82
83 Cluster Wide Setup
84 ~~~~~~~~~~~~~~~~~~
85
86 The cluster wide firewall configuration is stored at:
87
88 /etc/pve/firewall/cluster.fw
89
90 The configuration can contain the following sections:
91
92 '[OPTIONS]'::
93
94 This is used to set cluster wide firewall options.
95
96 include::pve-firewall-cluster-opts.adoc[]
97
98 NOTE: The firewall is completely disabled by default, so you need to
99 set the enable option here:
100
101 ----
102 [OPTIONS]
103 # enable firewall (cluster wide setting, default is disabled)
104 enable: 1
105 ----
106
107 '[RULES]'::
108
109 This sections contains cluster wide firewall rules for all nodes.
110
111 '[IPSET <name>]'::
112
113 Cluster wide IP set definitions.
114
115 '[GROUP <name>]'::
116
117 Cluster wide security group definitions.
118
119 '[ALIASES]'::
120
121 Cluster wide Alias definitions.
122
123 Host specific Configuration
124 ~~~~~~~~~~~~~~~~~~~~~~~~~~~
125
126 Host related configuration is read from:
127
128 /etc/pve/nodes/<nodename>/host.fw
129
130 This is useful if you want to overwrite rules from 'cluster.fw'
131 config. You can also increase log verbosity, and set netfilter related
132 options.
133
134
135 VM/Container configuration
136 ~~~~~~~~~~~~~~~~~~~~~~~~~~
137
138 VM firewall configuration is read from:
139
140 /etc/pve/firewall/<VMID>.fw
141
142 and contains the following data:
143
144 * IP set definitions
145 * Alias definitions
146 * Firewall rules for this VM
147 * VM specific options
148
149
150 Enabling the Firewall for VMs and Containers
151 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
152
153 You need to enable the firewall on the virtual network interface configuration
154 in addition to the general 'Enable Firewall' option in the 'Options' tab.
155
156
157 Firewall Rules
158 --------------
159
160 Firewall rules consists of a direction (`IN` or `OUT`) and an
161 action (`ACCEPT`, `DENY`, `REJECT`). You can also specify a macro
162 name. Macros contain predifined sets of rules and options. Rules can be disabled by prefixing them with '|'.
163
164 .Firewall rules syntax
165 ----
166 [RULES]
167
168 DIRECTION ACTION [OPTIONS]
169 |DIRECTION ACTION [OPTIONS] # disabled rule
170
171 DIRECTION MACRO(ACTION) [OPTIONS] # use predefined macro
172 ----
173
174 The following options can be used to refine rule matches.
175
176 include::pve-firewall-rules-opts.adoc[]
177
178 Here are some examples:
179
180 ----
181 [RULES]
182 IN SSH(ACCEPT) -i net0
183 IN SSH(ACCEPT) -i net0 # a comment
184 IN SSH(ACCEPT) -i net0 -source 192.168.2.192 # only allow SSH from 192.168.2.192
185 IN SSH(ACCEPT) -i net0 -source 10.0.0.1-10.0.0.10 # accept SSH for ip range
186 IN SSH(ACCEPT) -i net0 -source 10.0.0.1,10.0.0.2,10.0.0.3 #accept ssh for ip list
187 IN SSH(ACCEPT) -i net0 -source +mynetgroup # accept ssh for ipset mynetgroup
188 IN SSH(ACCEPT) -i net0 -source myserveralias #accept ssh for alias myserveralias
189
190 |IN SSH(ACCEPT) -i net0 # disabled rule
191
192 IN DROP # drop all incoming packages
193 OUT ACCEPT # accept all outgoing packages
194 ----
195
196 Security Groups
197 ---------------
198
199 A security group is a collection of rules, defined at cluster level, which
200 can be used in all VMs' rules. For example you can define a group named
201 `webserver` with rules to open the http and https ports.
202
203 ----
204 # /etc/pve/firewall/cluster.fw
205
206 [group webserver]
207 IN ACCEPT -p tcp -dport 80
208 IN ACCEPT -p tcp -dport 443
209 ----
210
211 Then, you can add this group to a VM's firewall
212
213 ----
214 # /etc/pve/firewall/<VMID>.fw
215
216 [RULES]
217 GROUP webserver
218 ----
219
220
221 IP Aliases
222 ----------
223
224 IP Aliases allow you to associate IP addresses of networks with a
225 name. You can then refer to those names:
226
227 * inside IP set definitions
228 * in `source` and `dest` properties of firewall rules
229
230 Standard IP alias `local_network`
231 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
232
233 This alias is automatically defined. Please use the following command
234 to see assigned values:
235
236 ----
237 # pve-firewall localnet
238 local hostname: example
239 local IP address: 192.168.2.100
240 network auto detect: 192.168.0.0/20
241 using detected local_network: 192.168.0.0/20
242 ----
243
244 The firewall automatically sets up rules to allow everything needed
245 for cluster communication (corosync, API, SSH) using this alias.
246
247 The user can overwrite these values in the cluster.fw alias
248 section. If you use a single host on a public network, it is better to
249 explicitly assign the local IP address
250
251 ----
252 # /etc/pve/firewall/cluster.fw
253 [ALIASES]
254 local_network 1.2.3.4 # use the single ip address
255 ----
256
257 IP Sets
258 -------
259
260 IP sets can be used to define groups of networks and hosts. You can
261 refer to them with `+name` in the firewall rules' `source` and `dest`
262 properties.
263
264 The following example allows HTTP traffic from the `management` IP
265 set.
266
267 IN HTTP(ACCEPT) -source +management
268
269 Standard IP set `management`
270 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
271
272 This IP set applies only to host firewalls (not VM firewalls). Those
273 ips are allowed to do normal management tasks (PVE GUI, VNC, SPICE,
274 SSH).
275
276 The local cluster network is automatically added to this IP set (alias
277 `cluster_network`), to enable inter-host cluster
278 communication. (multicast,ssh,...)
279
280 ----
281 # /etc/pve/firewall/cluster.fw
282
283 [IPSET management]
284 192.168.2.10
285 192.168.2.10/24
286 ----
287
288 Standard IP set 'blacklist'
289 ~~~~~~~~~~~~~~~~~~~~~~~~~~~
290
291 Traffic from these ips is dropped by every host's and VM's firewall.
292
293 ----
294 # /etc/pve/firewall/cluster.fw
295
296 [IPSET blacklist]
297 77.240.159.182
298 213.87.123.0/24
299 ----
300
301 [[ipfilter-section]]
302 Standard IP set 'ipfilter-net*'
303 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
304
305 These filters belong to a VM's network interface and are mainly used to prevent
306 IP spoofing. If such a set exists for an interface then any outgoing traffic
307 with a source IP not matching its interface's corresponding ipfilter set will
308 be dropped.
309
310 For containers with configured IP addresses these sets, if they exist (or are
311 activated via the general `IP Filter` option in the VM's firewall's 'options'
312 tab), implicitly contain the associated IP addresses.
313
314 For both virtual machines and containers they also implicitly contain the
315 standard MAC-derived IPv6 link-local address in order to allow the neighbor
316 discovery protocol to work.
317
318 ----
319 /etc/pve/firewall/<VMID>.fw
320
321 [IPSET ipfilter-net0] # only allow specified IPs on net0
322 192.168.2.10
323 ----
324
325
326 Services and Commands
327 ---------------------
328
329 The firewall runs two service daemons on each node:
330
331 * pvefw-logger: NFLOG daemon (ulogd replacement).
332 * pve-firewall: updates iptables rules
333
334 There is also a CLI command named 'pve-firewall', which can be used to
335 start and stop the firewall service:
336
337 # pve-firewall start
338 # pve-firewall stop
339
340 To get the status use:
341
342 # pve-firewall status
343
344 The above command reads and compiles all firewall rules, so you will
345 see warnings if your firewall configuration contains any errors.
346
347 If you want to see the generated iptables rules you can use:
348
349 # iptables-save
350
351
352 Tips and Tricks
353 ---------------
354
355 How to allow FTP
356 ~~~~~~~~~~~~~~~~
357
358 FTP is an old style protocol which uses port 21 and several other dynamic ports. So you
359 need a rule to accept port 21. In addition, you need to load the 'ip_conntrack_ftp' module.
360 So please run:
361
362 modprobe ip_conntrack_ftp
363
364 and add `ip_conntrack_ftp` to '/etc/modules' (so that it works after a reboot) .
365
366
367 Suricata IPS integration
368 ~~~~~~~~~~~~~~~~~~~~~~~~
369
370 If you want to use the http://suricata-ids.org/[Suricata IPS]
371 (Intrusion Prevention System), it's possible.
372
373 Packets will be forwarded to the IPS only after the firewall ACCEPTed
374 them.
375
376 Rejected/Dropped firewall packets don't go to the IPS.
377
378 Install suricata on proxmox host:
379
380 ----
381 # apt-get install suricata
382 # modprobe nfnetlink_queue
383 ----
384
385 Don't forget to add `nfnetlink_queue` to '/etc/modules' for next reboot.
386
387 Then, enable IPS for a specific VM with:
388
389 ----
390 # /etc/pve/firewall/<VMID>.fw
391
392 [OPTIONS]
393 ips: 1
394 ips_queues: 0
395 ----
396
397 `ips_queues` will bind a specific cpu queue for this VM.
398
399 Available queues are defined in
400
401 ----
402 # /etc/default/suricata
403 NFQUEUE=0
404 ----
405
406 Avoiding link-local addresses on tap and veth devices
407 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
408
409 With IPv6 enabled by default every interface gets a MAC-derived link local
410 address. However, most devices on a typical {pve} setup are connected to a
411 bridge and so the bridge is the only interface which really needs one.
412
413 To 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
415 traffic from passing through the interface when routing or bridging, so the
416 only noticeable effect will be the removal of the link local address.
417
418 The easiest method of achieving this setting for all newly started VMs is to
419 set it for the `default` interface configuration and enabling it explicitly on
420 the interfaces which need it. This is also the case for other settings such as
421 `forwarding`, `accept_ra` or `autoconf`.
422
423 Here's a possible setup:
424 ----
425 # /etc/sysconf.d/90-ipv6.conf
426
427 net.ipv6.conf.default.forwarding = 0
428 net.ipv6.conf.default.proxy_ndp = 0
429 net.ipv6.conf.default.autoconf = 0
430 net.ipv6.conf.default.disable_ipv6 = 1
431 net.ipv6.conf.default.accept_ra = 0
432
433 net.ipv6.conf.lo.disable_ipv6 = 0
434 ----
435
436 ----
437 # /etc/network/interfaces
438 (...)
439 iface 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 ----
447
448
449 Notes on IPv6
450 -------------
451
452 The firewall contains a few IPv6 specific options. One thing to note is that
453 IPv6 does not use the ARP protocol anymore, and instead uses NDP (Neighbor
454 Discovery Protocol) which works on IP level and thus needs IP addresses to
455 succeed. For this purpose link-local addresses derived from the interface's MAC
456 address are used. By default the 'NDP' option is enabled on both host and VM
457 level to allow neighbor discovery (NDP) packets to be sent and received.
458
459 Beside neighbor discovery NDP is also used for a couple of other things, like
460 autoconfiguration and advertising routers.
461
462 By default VMs are allowed to send out router solicitation messages (to query
463 for a router), and to receive router advetisement packets. This allows them to
464 use stateless auto configuration. On the other hand VMs cannot advertise
465 themselves as routers unless the 'Allow Router Advertisement' (`radv: 1`) option
466 is set.
467
468 As for the link local addresses required for NDP, there's also an 'IP Filter'
469 (`ipfilter: 1`) option which can be enabled which has the same effect as adding
470 an `ipfilter-net*` ipset for each of the VM's network interfaces containing the
471 corresponding link local addresses. (See the
472 <<ipfilter-section,Standard IP set 'ipfilter-net*'>> section for details.)
473
474
475 Ports used by Proxmox VE
476 ------------------------
477
478 * Web interface: 8006
479 * VNC Web console: 5900-5999
480 * SPICE proxy: 3128
481 * sshd (used for cluster actions): 22
482 * rpcbind: 111
483 * corosync multicast (if you run a cluster): 5404, 5405 UDP
484
485
486 ifdef::manvolnum[]
487
488 Macro Definitions
489 -----------------
490
491 include::pve-firewall-macros.adoc[]
492
493
494 include::pve-copyright.adoc[]
495
496 endif::manvolnum[]