restricting a match to an IPv6 address prefix. A netmask is specified
as a CIDR block (e.g. \fB2001:db8:3c4d:1::/64\fR).
.
+.IP \fBipv6_label=\fIlabel\fR
+When \fBdl_type\fR is 0x86dd (possibly via shorthand, e.g., \fBipv6\fR
+or \fBtcp6\fR), matches IPv6 flow label \fIlabel\fR.
+.
.IP \fBnd_target=\fIipv6\fR
When \fBdl_type\fR, \fBnw_proto\fR, and \fBicmp_type\fR specify
IPv6 Neighbor Discovery (ICMPv6 type 135 or 136), matches the target address