[p4] begin icmp6 checksum

doc/plan.org

@@ -66,6 +66,7 @@
 **** DONE Parse icmp
 **** DONE Parse icmpv6
 **** DONE Add (static) egress configuration
+**** TODO Calculate ICMP6 checksums
 **** TODO Make switch answer icmp6 echo request for
 **** TODO Make switch answer icmp echo request for
 **** TODO Add default route for v6 and v4 hosts
@@ -144,6 +145,29 @@ user@T:~# iptables  -t mangle -A PREROUTING \
 **** Static mappings
       - likely need table(s)
       - need tcp & udp translation
+**** ICMPv6
+Different lengths possible
+
+[20:35] line:~% ping -6 -s 20 ::1
+PING ::1(::1) 20 data bytes
+28 bytes from ::1: icmp_seq=1 ttl=64 time=0.045 ms
+28 bytes from ::1: icmp_seq=2 ttl=64 time=0.064 ms
+^C
+--- ::1 ping statistics ---
+2 packets transmitted, 2 received, 0% packet loss, time 1018ms
+rtt min/avg/max/mdev = 0.045/0.054/0.064/0.012 ms
+[20:36] line:~% ping -6 -s 80 ::1
+PING ::1(::1) 80 data bytes
+88 bytes from ::1: icmp_seq=1 ttl=64 time=0.053 ms
+88 bytes from ::1: icmp_seq=2 ttl=64 time=0.095 ms
+^C
+--- ::1 ping statistics ---
+2 packets transmitted, 2 received, 0% packet loss, time 1001ms
+rtt min/avg/max/mdev = 0.053/0.074/0.095/0.021 ms
+[20:36] line:~%
+
+Different checksum in most packets.
+
 ***** Hosts
 ****** Left side: IPv6
 ****** Right side: IPv4
@@ -157,6 +181,8 @@ user@T:~# iptables  -t mangle -A PREROUTING \
 **** RFC 6052: https://tools.ietf.org/html/rfc6052  IPv6 Addressing of IPv4/IPv6 Translators
 **** RFC 6586 for deployment experiences using Stateful NAT64.
 **** RFC 7757 Explicit Address Mappings for Stateless IP/ICMP Translation
+**** RFC 4443 ICMPv6 https://tools.ietf.org/html/rfc4443
+**** RFC 2460 IPv6 (Checksum https://tools.ietf.org/html/rfc2460#section-8.1)
 **** EAMT/Jool: https://www.jool.mx/en/eamt.html
 * Proposal / task description
 ** Task description for mystudies