X-Git-Url: https://git.proxmox.com/?a=blobdiff_plain;ds=sidebyside;f=pve-firewall.adoc;h=4e551a79105b4e45b336a7459a204ce316dcabe9;hb=224128ce0994a66e2a91e82845a39afcc32b0010;hp=36a4f3c4bb24e5cb4beb27e3a66789e7c0142681;hpb=58b16f713fa7e39236f3dab2b33e55ef273f7377;p=pve-docs.git diff --git a/pve-firewall.adoc b/pve-firewall.adoc index 36a4f3c..4e551a7 100644 --- a/pve-firewall.adoc +++ b/pve-firewall.adoc @@ -42,6 +42,10 @@ firewall solution. NOTE: If you enable the firewall, all traffic is blocked by default, except WebGUI(8006) and ssh(22) from your local network. +The firewall has full support for IPv4 and IPv6. IPv6 support is fully +transparent, and we filter traffic for both protocols by default. So +there is no need to maintain a different set of rules for IPv6. + Zones ----- @@ -60,17 +64,6 @@ For each zone, you can define firewall rules for incoming and/or outgoing traffic. -Ports used by Proxmox VE ------------------------- - -* Web interface: 8006 -* VNC Web console: 5900-5999 -* SPICE proxy: 3128 -* sshd (used for cluster actions): 22 -* rpcbind: 111 -* corosync multicast (if you run a cluster): 5404, 5405 UDP - - Configuration ------------- @@ -130,32 +123,40 @@ in addition to the general 'Enable Firewall' option in the 'Options' tab. Firewall Rules ~~~~~~~~~~~~~~ -Any firewall rule consists of a direction (`IN` or `OUT`) and an -action (`ACCEPT`, `DENY`, `REJECT`). Additional options can be used to -refine rule matches. Here are some examples: +Firewall rules consists of a direction (`IN` or `OUT`) and an +action (`ACCEPT`, `DENY`, `REJECT`). You can also specify a macro +name. Macros contain predifined sets of rules and options. Rules can be disabled by prefixing them with '|'. +.Firewall rules syntax ---- [RULES] -#TYPE ACTION [OPTIONS] -#TYPE MACRO(ACTION) [OPTIONS] +DIRECTION ACTION [OPTIONS] +|DIRECTION ACTION [OPTIONS] # disabled rule -# -i -# -source -# -dest -# -p -# -dport -# -sport +DIRECTION MACRO(ACTION) [OPTIONS] # use predefined macro +---- + +The following options can be used to refine rule matches. + +include::pve-firewall-rules-opts.adoc[] +Here are some examples: + +---- +[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 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 +mynetgroup # accept ssh for ipset mynetgroup -IN SSH(ACCEPT) -i net0 -source myserveralias #accept ssh for alias myserveralias +IN SSH(ACCEPT) -i net0 -source +mynetgroup # accept ssh for ipset mynetgroup +IN SSH(ACCEPT) -i net0 -source myserveralias #accept ssh for alias myserveralias |IN SSH(ACCEPT) -i net0 # disabled rule + +IN DROP # drop all incoming packages +OUT ACCEPT # accept all outgoing packages ---- Security Groups @@ -263,10 +264,22 @@ Traffic from these ips is dropped by every host's and VM's firewall. 213.87.123.0/24 ---- -Standard IP set 'ipfilter' -^^^^^^^^^^^^^^^^^^^^^^^^^^ +[[ipfilter-section]] +Standard IP set 'ipfilter-net*' +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +These filters belong to a VM's network interface and are mainly used to prevent +IP spoofing. If such a set exists for an interface then any outgoing traffic +with a source IP not matching its interface's corresponding ipfilter set will +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' +tab), implicitly contain the associated IP addresses. -This ipset is used to prevent ip spoofing +For both virtual machines and containers they also implicitly contain the +standard MAC-derived IPv6 link-local address in order to allow the neighbor +discovery protocol to work. ---- /etc/pve/firewall/.fw @@ -353,8 +366,92 @@ Available queues are defined in NFQUEUE=0 ---- +Notes on IPv6 +^^^^^^^^^^^^^ + +The firewall contains a few IPv6 specific options. One thing to note is that +IPv6 does not use the ARP protocol anymore, and instead uses NDP (Neighbor +Discovery Protocol) which works on IP level and thus needs IP addresses to +succeed. For this purpose link-local addresses derived from the interface's MAC +address are used. By default the 'NDP' option is enabled on both host and VM +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. + +By default VMs are allowed to send out router solicitation messages (to query +for a router), and to receive router advetisement packets. This allows them to +use stateless auto configuration. On the other hand VMs cannot advertise +themselves as routers unless the 'Allow Router Advertisement' (`radv: 1`) option +is set. + +As for the link local addresses required for NDP, there's also an 'IP Filter' +(`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 +<> section for details.) + +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 +(...) +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 +(...) +---- + +Ports used by Proxmox VE +------------------------ + +* Web interface: 8006 +* VNC Web console: 5900-5999 +* SPICE proxy: 3128 +* sshd (used for cluster actions): 22 +* rpcbind: 111 +* corosync multicast (if you run a cluster): 5404, 5405 UDP + ifdef::manvolnum[] -include::copyright.adoc[] -endif::manvolnum[] +Macro Definitions +----------------- + +include::pve-firewall-macros.adoc[] + + +include::pve-copyright.adoc[] + +endif::manvolnum[]