ICMPv6, type 2 (Packet Too Big)
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From http://test-ipv6.com/
IPv6 firewalls need to permit ICMPv6, type 2 (Packet Too Big) to work correctly with the public Internet. If you are implementing the IPv6 firewall for your web site, your enterprise, or other organization, please permit this specific ICMPv6 message, even if you by default block other types of ICMP.
When I try to set up a firewall rule for ICMPv6, I can't find a type "Packet Too Big", is this listed under a different name, or does this need to be added to the pop-up list of ICMP types?
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There are a few ICMPv6 types that are required and thus they are allowed by default in pfSense.
/etc/inc/filter.inc
# IPv6 ICMP is not auxilary, it is required for operation # See man icmp6(4) # 1 unreach Destination unreachable # 2 toobig Packet too big # 128 echoreq Echo service request # 129 echorep Echo service reply # 133 routersol Router solicitation # 134 routeradv Router advertisement # 135 neighbrsol Neighbor solicitation # 136 neighbradv Neighbor advertisement pass quick inet6 proto ipv6-icmp from any to any icmp6-type {1,2,135,136} keep state # Allow only bare essential icmpv6 packets (NS, NA, and RA, echoreq, echorep) pass out quick inet6 proto ipv6-icmp from fe80::/10 to fe80::/10 icmp6-type {129,133,134,135,136} keep state pass out quick inet6 proto ipv6-icmp from fe80::/10 to ff02::/16 icmp6-type {129,133,134,135,136} keep state pass in quick inet6 proto ipv6-icmp from fe80::/10 to fe80::/10 icmp6-type {128,133,134,135,136} keep state pass in quick inet6 proto ipv6-icmp from ff02::/16 to fe80::/10 icmp6-type {128,133,134,135,136} keep state pass in quick inet6 proto ipv6-icmp from fe80::/10 to ff02::/16 icmp6-type {128,133,134,135,136} keep state
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