#!/usr/sbin/nft -f
+<% unless @interfaces.empty? -%>
define external-interfaces = { <%= @interfaces.sort.uniq.join(", ") %> }
-
-define ip-private-addresses = { 10.0.0.0/8, 127.0.0.0/8, 169.254.0.0/16, 172.16.0.0/12, 192.0.2.0/24, 192.168.0.0/16 }
+<% end -%>
+# Exclude 169.254.169.0/24 from ip-private-addresses as is widely by cloud providers.
+define ip-private-addresses = { 0.0.0.0, 10.0.0.0/8, 127.0.0.0/8, 169.254.0.0-169.254.168.255, 169.254.170.0-169.254.255.255, 172.16.0.0/12, 192.0.2.0/24, 192.168.0.0/16 }
+define ip-multicast-addresses = { 224.0.0.0/4 }
define ip6-private-addresses = { 2001:db8::/32, fc00::/7 }
+define ip6-multicast-addresses = { ff00::/8 }
-define ip-osm-addresses = { <%= Array(@hosts[:inet]).sort.join(", ") %> }
-define ip6-osm-addresses = { <%= Array(@hosts[:inet6]).sort.join(", ") %> }
+table inet chef-filter {
+ set ip-osm-addresses {
+ type ipv4_addr
+<% unless Array(@hosts[:inet]).empty? -%>
+ elements = { <%= Array(@hosts[:inet]).sort.join(", ") %> }
+<% end -%>
+ }
-flush ruleset
+ set ip6-osm-addresses {
+ type ipv6_addr
+<% unless Array(@hosts[:inet6]).empty? -%>
+ elements = { <%= Array(@hosts[:inet6]).sort.join(", ") %> }
+<% end -%>
+ }
-table inet filter {
- set ip-blacklist {
+ set ip-blocklist {
type ipv4_addr
- flags dynamic
+ flags interval
}
- set ip6-blacklist {
+ set ip6-blocklist {
type ipv6_addr
- flags dynamic
+ flags interval
}
-<%- node[:networking][:firewall][:sets].each do |set| %>
- set <%= set %> {
-<%- if set.end_with?("-ip") %>
+ set ratelimit-icmp-echo-ip {
type ipv4_addr
-<%- elsif set.end_with?("-ip6") %>
+ flags dynamic
+ timeout 120s
+ }
+
+ set ratelimit-icmp-echo-ip6 {
type ipv6_addr
-<%- end %>
flags dynamic
+ timeout 120s
+ }
+
+<% node[:networking][:firewall][:sets].each do |set| -%>
+ set <%= set[:name] %> {
+ type <%= set[:type] %>
+<% if set[:flags] -%>
+ flags <%= set[:flags].join(", ") %>
+<% end -%>
+<% if set[:timeout] -%>
+ timeout <%= set[:timeout] %>s
+<% end -%>
}
-<%- end %>
+<% end -%>
+
+<% node[:networking][:firewall][:helpers].each do |helper| -%>
+ ct helper <%= helper[:name] %> {
+ type "<%= helper[:helper] %>" protocol <%= helper[:protocol] %>
+ }
+
+<% end -%>
chain log-and-drop {
- limit rate 1/second log
+ limit rate 1/second log level notice
drop
}
chain log-and-reject {
- limit rate 1/second log
+ limit rate 1/second log level notice
reject
}
chain incoming {
- ip saddr { $ip-private-addresses } jump log-and-drop
- ip6 saddr { $ip6-private-addresses } jump log-and-drop
+<% if node[:networking][:firewall][:allowlist].empty? -%>
+ ip saddr { $ip-private-addresses, $ip-multicast-addresses } jump log-and-drop
+<% else -%>
+ ip saddr { $ip-private-addresses, $ip-multicast-addresses } ip saddr != { <%= node[:networking][:firewall][:allowlist].sort.join(", ") %> } jump log-and-drop
+<% end -%>
+ ip6 saddr { $ip6-private-addresses, $ip6-multicast-addresses } jump log-and-drop
- ip saddr @ip-blacklist jump log-and-drop
- ip6 saddr @ip6-blacklist jump log-and-drop
+ ip saddr @ip-blocklist jump log-and-drop
+ ip6 saddr @ip6-blocklist jump log-and-drop
- ct state { established, related } accept
+ icmp type { echo-request } update @ratelimit-icmp-echo-ip { ip saddr limit rate 1/second } accept
+ icmp type { echo-request } drop
- icmp type { destination-unreachable } accept
icmpv6 type { nd-neighbor-solicit, nd-neighbor-advert, nd-router-solicit, nd-router-advert } accept
+ icmpv6 type { echo-request } update @ratelimit-icmp-echo-ip6 { ip6 saddr limit rate 1/second } accept
+ icmpv6 type { echo-request } drop
- icmp type { echo-request } limit rate 1/second accept
- icmpv6 type { echo-request } limit rate 1/second accept
+ ct state { established, related } accept
meta l4proto { icmp, icmpv6 } jump log-and-drop
-<%- node[:networking][:firewall][:incoming].uniq.each do |rule| %>
+ tcp flags & (fin|syn|rst|psh|ack|urg) == fin|psh|urg jump log-and-drop
+ tcp flags & (fin|syn|rst|psh|ack|urg) == 0x0 jump log-and-drop
+ tcp flags & (syn|rst) == syn|rst jump log-and-drop
+ tcp flags & (fin|rst) == fin|rst jump log-and-drop
+ tcp flags & (fin|syn) == fin|syn jump log-and-drop
+ tcp flags & (fin|psh|ack) == fin|psh jump log-and-drop
+ tcp sport 0 tcp flags & (fin|syn|rst|ack) == syn jump log-and-drop
+
+<% node[:networking][:firewall][:incoming].uniq.each do |rule| -%>
<%= rule %>
-<%- end %>
+<% end -%>
jump log-and-drop
}
chain outgoing {
+<% if node[:networking][:firewall][:allowlist].empty? -%>
ip daddr { $ip-private-addresses } jump log-and-drop
+<% else -%>
+ ip daddr { $ip-private-addresses } ip daddr != { <%= node[:networking][:firewall][:allowlist].sort.join(", ") %> } jump log-and-drop
+<% end -%>
ip6 daddr { $ip6-private-addresses } jump log-and-drop
-<%- node[:networking][:firewall][:outgoing].each do |rule| %>
+<% node[:networking][:firewall][:outgoing].each do |rule| -%>
<%= rule %>
-<%- end %>
+<% end -%>
accept
}
chain input {
type filter hook input priority filter;
- iif { $external-interfaces } jump incoming
+<% unless @interfaces.empty? -%>
+ iifname { $external-interfaces } jump incoming
+<% end -%>
accept
}
chain forward {
type filter hook forward priority filter;
- iif { $external-interfaces } jump incoming
- oif { $external-interfaces } jump outgoing
+<% unless @interfaces.empty? -%>
+ iifname { $external-interfaces } jump incoming
+ oifname { $external-interfaces } jump outgoing
+<% end -%>
accept
}
chain output {
type filter hook output priority filter;
- oif { $external-interfaces } jump outgoing
+<% unless @interfaces.empty? -%>
+ oifname { $external-interfaces } jump outgoing
+<% end -%>
accept
}
}
-<%- if node[:roles].include?("gateway") %>
+<% if node[:roles].include?("gateway") -%>
-table ip nat {
+table ip chef-nat {
chain postrouting {
type nat hook postrouting priority srcnat;
-<%- node.interfaces(:role => :external).each do |external| %>
-<%- node.interfaces(:role => :internal).each do |internal| %>
- oif { < %= external[:interface] %> } ip saddr { <%= internal[:network] %>/<%= internal[:prefix] %> } snat <%= external[:address] %>
-<%- end %>
-<%- end %>
+<% node.interfaces(:role => :external).each do |external| -%>
+<% node.ipaddresses(:role => :internal, :family => :inet).each do |internal| -%>
+ oifname { <%= external[:interface] %> } ip saddr { <%= internal.subnet %> } snat <%= external[:inet][:address] %>
+<% end -%>
+<% end -%>
}
}
-<%- end %>
+<% end -%>