+## Split local addresses into v4 and v6 lists.
+unset l4addr l6addr
+for a in $P_LADDR; do
+ case "$a" in
+ *:*) l6addr=${l6addr+$l6addr }$a ;;
+ *) l4addr=${l4addr+$l4addr }$a ;;
+ esac
+done
+
+## Determine the remote v4 and v6 addresses. We only allow one remote
+## address for each: others can be added as routes.
+unset r4addr r6addr
+for a in $P_RADDR; do
+ case "$a" in
+ *:*) r6addr=$a ;;
+ *) r4addr=$a ;;
+ esac
+done
+
+## Configure the first v4 address as point-to-point; add the others as plain
+## addresses.
+haveaddr4=nil
+set -- $l4addr
+case $#,${r4addr+set} in
+ [1-9]*,set)
+ ip addr add "$1" peer "$r4addr" dev "$ifname"
+ haveaddr4=t
+ shift
+ ;;
+esac
+for a in "$@"; do
+ ip addr add "$a/32" dev "$ifname"
+ haveaddr4=t
+done
+
+## IPv6 point-to-point links seem broken in Linux. Attach the local and
+## remote addresses by hand.
+haveaddr6=nil
+set -- $l6addr
+case $have6,$# in
+ t,[1-9]*)
+ for a in "$@"; do
+ ip addr add "$a/128" dev "$ifname"
+ haveaddr6=t
+ done
+ case ${r6addr+set} in
+ set) ip route add $r6addr/128 dev "$ifname" ;;
+ esac
+ ;;
+esac
+
+###--------------------------------------------------------------------------
+### Bring the interface up.
+
+case $haveaddr4,$haveaddr6 in
+ nil,nil)
+ ;;
+ *)