Fix icmp echo rate limiting

[chef.git] / cookbooks / networking / templates / default / nftables.conf.erb

diff --git a/cookbooks/networking/templates/default/nftables.conf.erb b/cookbooks/networking/templates/default/nftables.conf.erb
index 65d090db31d3cd6ed2b19b3ded337c516402e745..f1773f384826a905e83dbf91f17b001d7f725d70 100644 (file)
--- a/cookbooks/networking/templates/default/nftables.conf.erb
+++ b/cookbooks/networking/templates/default/nftables.conf.erb
@@ -1,13 +1,13 @@
 #!/usr/sbin/nft -f
 
+<%- unless @interfaces.empty? %>
 define external-interfaces = { <%= @interfaces.sort.uniq.join(", ") %> }
+<%- end %>
 
-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 }
-define ip6-private-addresses = { 2001:db8::/32, fc00::/7 }
-
-flush ruleset
+define ip-private-addresses = { 0.0.0.0, 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, 224.0.0.0/4 }
+define ip6-private-addresses = { 2001:db8::/32, fc00::/7, ff00::/8 }
 
-table inet filter {
+table inet chef-filter {
   set ip-osm-addresses {
     type ipv4_addr
 <%- unless Array(@hosts["inet"]).empty? %>
@@ -22,14 +22,26 @@ table inet filter {
 <%- end %>
   }
 
-  set ip-blacklist {
+  set ip-blocklist {
+    type ipv4_addr
+    flags interval
+  }
+
+  set ip6-blocklist {
+    type ipv6_addr
+    flags interval
+  }
+
+  set ratelimit-icmp-echo-ip {
     type ipv4_addr
     flags dynamic
+    timeout 120s
   }
 
-  set ip6-blacklist {
+  set ratelimit-icmp-echo-ip6 {
     type ipv6_addr
     flags dynamic
+    timeout 120s
   }
 
 <%- node[:networking][:firewall][:sets].each do |set| %>
@@ -40,6 +52,16 @@ table inet filter {
     type ipv6_addr
 <%- end %>
     flags dynamic
+<%- unless set.start_with?("connlimit-") %>
+    timeout 120s
+<%- end %>
+  }
+
+<%- end %>
+
+<%- node[:networking][:firewall][:helpers].each do |helper| %>
+  ct helper <%= helper[:name] %> {
+    type "<%= helper[:helper] %>" protocol <%= helper[:protocol] %>
   }
 
 <%- end %>
@@ -54,22 +76,35 @@ table inet filter {
   }
 
   chain incoming {
+<%- if node[:networking][:firewall][:allowlist].empty? %>
     ip saddr { $ip-private-addresses } jump log-and-drop
+<%- else %>
+    ip saddr { $ip-private-addresses } ip saddr != { <%= node[:networking][:firewall][:allowlist].sort.join(", ") %> } jump log-and-drop
+<%- end %>
     ip6 saddr { $ip6-private-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
 
+    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 %>
@@ -78,7 +113,11 @@ table inet filter {
   }
 
   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| %>
@@ -91,7 +130,9 @@ table inet filter {
   chain input {
     type filter hook input priority filter;
 
-    iif { $external-interfaces } jump incoming
+<%- unless @interfaces.empty? %>
+    iifname { $external-interfaces } jump incoming
+<%- end %>
 
     accept
   }
@@ -99,8 +140,10 @@ table inet filter {
   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
   }
@@ -108,20 +151,22 @@ table inet filter {
   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") %>
 
-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] %>
+<%- node.interfaces(:role => :external, :family => :inet).each do |external| %>
+<%- node.interfaces(:role => :internal, :family => :inet).each do |internal| %>
+    oifname { <%= external[:interface] %> } ip saddr { <%= internal[:network] %>/<%= internal[:prefix] %> } snat <%= external[:address] %>
 <%- end %>
 <%- end %>
   }