[19430] linux script significantly updated

1 files changed, 365 insertions, 276 deletions

diff --git a/client/scripts/linux b/client/scripts/linux
index e6792c67..1f118a21 100755
--- a/client/scripts/linux
+++ b/client/scripts/linux
@@ -22,295 +22,384 @@
 # 4. TIMEOUT not tested. ping has a flag I don't know, and I'm suspicious
 # of the $1 in its args.
 
-# 'ip' just looks too weird.  /sbin/ip looks less weird.
+# 5. Script refresh in 2017. The aliasing code was too convoluted and needs
+# to go away. Migrated DHCPv4 script to ip command from iproute2 suite.
+# This is based on Debian script with some tweaks. ifconfig is no longer
+# used. Everything is done using ip tool from ip-route2.
+
+# 'ip' just looks too weird. Also, we now have unit-tests! Those unit-tests
+# overwirte this line to use a fake ip-echo tool. It's also convenient
+# if your system holds ip tool in a non-standard location.
 ip=/sbin/ip
 
+# update /etc/resolv.conf based on received values
+# This updated version mostly follows Debian script by Andrew Pollock et al.
 make_resolv_conf() {
-  if [ x"$new_domain_name_servers" != x ]; then
-    cat /dev/null > /etc/resolv.conf.dhclient
-    chmod 644 /etc/resolv.conf.dhclient
-    if [ x"$new_domain_search" != x ]; then
-      echo search $new_domain_search >> /etc/resolv.conf.dhclient
-    elif [ x"$new_domain_name" != x ]; then
-      # Note that the DHCP 'Domain Name Option' is really just a domain
-      # name, and that this practice of using the domain name option as
-      # a search path is both nonstandard and deprecated.
-      echo search $new_domain_name >> /etc/resolv.conf.dhclient
+    local new_resolv_conf
+
+    # DHCPv4
+    if [ -n "$new_domain_search" ] || [ -n "$new_domain_name" ] ||
+       [ -n "$new_domain_name_servers" ]; then
+        new_resolv_conf=/etc/resolv.conf.dhclient-new
+        rm -f $new_resolv_conf
+
+        if [ -n "$new_domain_name" ]; then
+            echo domain ${new_domain_name%% *} >>$new_resolv_conf
+        fi
+
+        if [ -n "$new_domain_search" ]; then
+            if [ -n "$new_domain_name" ]; then
+                domain_in_search_list=""
+                for domain in $new_domain_search; do
+                    if [ "$domain" = "${new_domain_name}" ] ||
+                       [ "$domain" = "${new_domain_name}." ]; then
+                        domain_in_search_list="Yes"
+                    fi
+                done
+                if [ -z "$domain_in_search_list" ]; then
+                    new_domain_search="$new_domain_name $new_domain_search"
+                fi
+            fi
+            echo "search ${new_domain_search}" >> $new_resolv_conf
+        elif [ -n "$new_domain_name" ]; then
+            echo "search ${new_domain_name}" >> $new_resolv_conf
+        fi
+
+        if [ -n "$new_domain_name_servers" ]; then
+            for nameserver in $new_domain_name_servers; do
+                echo nameserver $nameserver >>$new_resolv_conf
+            done
+        else # keep 'old' nameservers
+            sed -n /^\w*[Nn][Aa][Mm][Ee][Ss][Ee][Rr][Vv][Ee][Rr]/p /etc/resolv.conf >>$new_resolv_conf
+        fi
+
+	if [ -f /etc/resolv.conf ]; then
+	    chown --reference=/etc/resolv.conf $new_resolv_conf
+	    chmod --reference=/etc/resolv.conf $new_resolv_conf
+	fi
+        mv -f $new_resolv_conf /etc/resolv.conf
+    # DHCPv6
+    elif [ -n "$new_dhcp6_domain_search" ] || [ -n "$new_dhcp6_name_servers" ]; then
+        new_resolv_conf=/etc/resolv.conf.dhclient-new
+        rm -f $new_resolv_conf
+
+        if [ -n "$new_dhcp6_domain_search" ]; then
+            echo "search ${new_dhcp6_domain_search}" >> $new_resolv_conf
+        fi
+
+        if [ -n "$new_dhcp6_name_servers" ]; then
+            for nameserver in $new_dhcp6_name_servers; do
+                # append %interface to link-local-address nameservers
+                if [ "${nameserver##fe80::}" != "$nameserver" ] ||
+                   [ "${nameserver##FE80::}" != "$nameserver" ]; then
+                    nameserver="${nameserver}%${interface}"
+                fi
+                echo nameserver $nameserver >>$new_resolv_conf
+            done
+        else # keep 'old' nameservers
+            sed -n /^\w*[Nn][Aa][Mm][Ee][Ss][Ee][Rr][Vv][Ee][Rr]/p /etc/resolv.conf >>$new_resolv_conf
+        fi
+
+	if [ -f /etc/resolv.conf ]; then
+            chown --reference=/etc/resolv.conf $new_resolv_conf
+            chmod --reference=/etc/resolv.conf $new_resolv_conf
+	fi
+        mv -f $new_resolv_conf /etc/resolv.conf
     fi
-    for nameserver in $new_domain_name_servers; do
-      echo nameserver $nameserver >>/etc/resolv.conf.dhclient
-    done
+}
 
-    mv /etc/resolv.conf.dhclient /etc/resolv.conf
-  elif [ "x${new_dhcp6_name_servers}" != x ] ; then
-    cat /dev/null > /etc/resolv.conf.dhclient6
-    chmod 644 /etc/resolv.conf.dhclient6
+# set host name
+set_hostname() {
+    local current_hostname
+
+    if [ -n "$new_host_name" ]; then
+        current_hostname=$(hostname)
+
+        # current host name is empty, '(none)' or 'localhost' or differs from new one from DHCP
+        if [ -z "$current_hostname" ] ||
+           [ "$current_hostname" = '(none)' ] ||
+           [ "$current_hostname" = 'localhost' ] ||
+           [ "$current_hostname" = "$old_host_name" ]; then
+           if [ "$new_host_name" != "$old_host_name" ]; then
+               hostname "$new_host_name"
+           fi
+        fi
+    fi
+}
+
+# run given script
+run_hook() {
+    local script
+    local exit_status
+    script="$1"
 
-    if [ "x${new_dhcp6_domain_search}" != x ] ; then
-      echo search ${new_dhcp6_domain_search} >> /etc/resolv.conf.dhclient6
+    if [ -f $script ]; then
+        . $script
     fi
-    shopt -s nocasematch 
-    for nameserver in ${new_dhcp6_name_servers} ; do
-      # If the nameserver has a link-local address
-      # add a <zone_id> (interface name) to it.
-      if  [[ "$nameserver" =~ ^fe80:: ]]
-      then
-	zone_id="%$interface"
-      else
-	zone_id=
-      fi
-      echo nameserver ${nameserver}$zone_id >> /etc/resolv.conf.dhclient6
-    done
-    shopt -u nocasematch 
-
-    mv /etc/resolv.conf.dhclient6 /etc/resolv.conf
-  fi
+
+    if [ -n "$exit_status" ] && [ "$exit_status" -ne 0 ]; then
+        logger -p daemon.err "$script returned non-zero exit status $exit_status"
+    fi
+
+    return $exit_status
+}
+
+# run scripts in given directory
+run_hookdir() {
+    local dir
+    local exit_status
+    dir="$1"
+
+    if [ -d "$dir" ]; then
+        for script in $(run-parts --list $dir); do
+            run_hook $script || true
+            exit_status=$?
+        done
+    fi
+
+    return $exit_status
 }
 
 # Must be used on exit.   Invokes the local dhcp client exit hooks, if any.
 exit_with_hooks() {
-  exit_status=$1
-  if [ -f /etc/dhclient-exit-hooks ]; then
-    . /etc/dhclient-exit-hooks
-  fi
-# probably should do something with exit status of the local script
-  exit $exit_status
-}
+    exit_status=$1
 
-# Invoke the local dhcp client enter hooks, if they exist.
-if [ -f /etc/dhclient-enter-hooks ]; then
-  exit_status=0
-  . /etc/dhclient-enter-hooks
-  # allow the local script to abort processing of this state
-  # local script must set exit_status variable to nonzero.
-  if [ $exit_status -ne 0 ]; then
-    exit $exit_status
-  fi
-fi
-
-###
-### DHCPv4 Handlers
-###
-
-if [ x$new_broadcast_address != x ]; then
-  new_broadcast_arg="broadcast $new_broadcast_address"
-fi
-if [ x$old_broadcast_address != x ]; then
-  old_broadcast_arg="broadcast $old_broadcast_address"
-fi
-if [ x$new_subnet_mask != x ]; then
-  new_subnet_arg="netmask $new_subnet_mask"
-fi
-if [ x$old_subnet_mask != x ]; then
-  old_subnet_arg="netmask $old_subnet_mask"
-fi
-if [ x$alias_subnet_mask != x ]; then
-  alias_subnet_arg="netmask $alias_subnet_mask"
-fi
-if [ x$new_interface_mtu != x ]; then
-  mtu_arg="mtu $new_interface_mtu"
-fi
-if [ x$IF_METRIC != x ]; then
-  metric_arg="metric $IF_METRIC"
-fi
-
-if [ x$reason = xMEDIUM ]; then
-  # Linux doesn't do mediums (ok, ok, media).
-  exit_with_hooks 0
-fi
-
-if [ x$reason = xPREINIT ]; then
-  if [ x$alias_ip_address != x ]; then
-    # Bring down alias interface. Its routes will disappear too.
-    ifconfig $interface:0- inet 0
-  fi
-  ifconfig $interface 0 up
-
-  # We need to give the kernel some time to get the interface up.
-  sleep 1
-
-  exit_with_hooks 0
-fi
-
-if [ x$reason = xARPCHECK ] || [ x$reason = xARPSEND ]; then
-  exit_with_hooks 0
-fi
-  
-if [ x$reason = xBOUND ] || [ x$reason = xRENEW ] || \
-   [ x$reason = xREBIND ] || [ x$reason = xREBOOT ]; then
-  current_hostname=`hostname`
-  if [ x$current_hostname = x ] || \
-     [ x$current_hostname = "x(none)" ] || \
-     [ x$current_hostname = xlocalhost ] || \
-     [ x$current_hostname = x$old_host_name ]; then
-    if [ x$new_host_name != x$old_host_name ]; then
-      hostname "$new_host_name"
+    # Source the documented exit-hook script, if it exists
+    if ! run_hook /etc/dhclient-exit-hooks; then
+        exit_status=$?
     fi
-  fi
-    
-  if [ x$old_ip_address != x ] && [ x$alias_ip_address != x ] && \
-		[ x$alias_ip_address != x$old_ip_address ]; then
-    # Possible new alias. Remove old alias.
-    ifconfig $interface:0- inet 0
-  fi
-  if [ x$old_ip_address != x ] && [ x$old_ip_address != x$new_ip_address ]; then
-    # IP address changed. Bringing down the interface will delete all routes,
-    # and clear the ARP cache.
-    ifconfig $interface inet 0 down
-
-  fi
-  if [ x$old_ip_address = x ] || [ x$old_ip_address != x$new_ip_address ] || \
-     [ x$reason = xBOUND ] || [ x$reason = xREBOOT ]; then
-
-    ifconfig $interface inet $new_ip_address $new_subnet_arg \
-					$new_broadcast_arg $mtu_arg
-    # Add a network route to the computed network address.
-    for router in $new_routers; do
-      if [ "x$new_subnet_mask" = "x255.255.255.255" ] ; then
-	route add -host $router dev $interface
-      fi
-      route add default gw $router $metric_arg dev $interface
-    done
-  else
-    # we haven't changed the address, have we changed other options           
-    # that we wish to update?
-    if [ x$new_routers != x ] && [ x$new_routers != x$old_routers ] ; then
-      # if we've changed routers delete the old and add the new.
-      for router in $old_routers; do
-        route del default gw $router
-      done
-      for router in $new_routers; do
-        if [ "x$new_subnet_mask" = "x255.255.255.255" ] ; then
-	  route add -host $router dev $interface
-	fi
-	route add default gw $router $metric_arg dev $interface
-      done
-    fi
-  fi
-  if [ x$new_ip_address != x$alias_ip_address ] && [ x$alias_ip_address != x ];
-   then
-    ifconfig $interface:0- inet 0
-    ifconfig $interface:0 inet $alias_ip_address $alias_subnet_arg
-    route add -host $alias_ip_address $interface:0
-  fi
-  make_resolv_conf
-  exit_with_hooks 0
-fi
-
-if [ x$reason = xEXPIRE ] || [ x$reason = xFAIL ] || [ x$reason = xRELEASE ] \
-   || [ x$reason = xSTOP ]; then
-  if [ x$alias_ip_address != x ]; then
-    # Turn off alias interface.
-    ifconfig $interface:0- inet 0
-  fi
-  if [ x$old_ip_address != x ]; then
-    # Shut down interface, which will delete routes and clear arp cache.
-    ifconfig $interface inet 0 down
-  fi
-  if [ x$alias_ip_address != x ]; then
-    ifconfig $interface:0 inet $alias_ip_address $alias_subnet_arg
-    route add -host $alias_ip_address $interface:0
-  fi
-  exit_with_hooks 0
-fi
-
-if [ x$reason = xTIMEOUT ]; then
-  if [ x$alias_ip_address != x ]; then
-    ifconfig $interface:0- inet 0
-  fi
-  ifconfig $interface inet $new_ip_address $new_subnet_arg \
-					$new_broadcast_arg $mtu_arg
-  set $new_routers
-  if ping -q -c 1 $1; then
-    if [ x$new_ip_address != x$alias_ip_address ] && \
-			[ x$alias_ip_address != x ]; then
-      ifconfig $interface:0 inet $alias_ip_address $alias_subnet_arg
-      route add -host $alias_ip_address dev $interface:0
+
+    # Now run scripts in the Debian-specific directory.
+    if ! run_hookdir /etc/dhclient-exit-hooks.d; then
+        exit_status=$?
     fi
-    for router in $new_routers; do
-      if [ "x$new_subnet_mask" = "x255.255.255.255" ] ; then
-	route add -host $router dev $interface
-      fi
-      route add default gw $router $metric_arg dev $interface
-    done
-    make_resolv_conf
-    exit_with_hooks 0
-  fi
-  ifconfig $interface inet 0 down
-  exit_with_hooks 1
-fi
-
-###
-### DHCPv6 Handlers
-###
-
-if [ x$reason = xPREINIT6 ] ; then
-  # Ensure interface is up.
-  ${ip} link set ${interface} up
-
-  # Remove any stale addresses from aborted clients.
-  ${ip} -f inet6 addr flush dev ${interface} scope global permanent
-
-  exit_with_hooks 0
-fi
-
-if [ x${old_ip6_prefix} != x ] || [ x${new_ip6_prefix} != x ] ; then
-    echo Prefix ${reason} old=${old_ip6_prefix} new=${new_ip6_prefix}
-
-    exit_with_hooks 0
-fi
-
-if [ x$reason = xBOUND6 ] ; then
-  if [ x${new_ip6_address} = x ] || [ x${new_ip6_prefixlen} = x ] ; then
-    exit_with_hooks 2;
-  fi
-
-  ${ip} -f inet6 addr add ${new_ip6_address}/${new_ip6_prefixlen} \
-	dev ${interface} scope global
-
-  # Check for nameserver options.
-  make_resolv_conf
-
-  exit_with_hooks 0
-fi
-
-if [ x$reason = xRENEW6 ] || [ x$reason = xREBIND6 ] ; then
-  if [ x${new_ip6_address} != x ] && [ x${new_ip6_prefixlen} != x ] ; then
-    ${ip} -f inet6 addr add ${new_ip6_address}/${new_ip6_prefixlen} \
-	dev ${interface} scope global
-  fi
-
-  # Make sure nothing has moved around on us.
-
-  # Nameservers/domains/etc.
-  if [ "x${new_dhcp6_name_servers}" != "x${old_dhcp6_name_servers}" ] ||
-     [ "x${new_dhcp6_domain_search}" != "x${old_dhcp6_domain_search}" ] ; then
-    make_resolv_conf
-  fi
-
-  exit_with_hooks 0
-fi
-
-if [ x$reason = xDEPREF6 ] ; then
-  if [ x${new_ip6_prefixlen} = x ] ; then
-    exit_with_hooks 2;
-  fi
-
-  ${ip} -f inet6 addr change ${new_ip6_address}/${new_ip6_prefixlen} \
-       dev ${interface} scope global preferred_lft 0
-
-  exit_with_hooks 0
-fi
-
-if [ x$reason = xEXPIRE6 -o x$reason = xRELEASE6 -o x$reason = xSTOP6 ] ; then
-  if [ x${old_ip6_address} = x ] || [ x${old_ip6_prefixlen} = x ] ; then
-    exit_with_hooks 2;
-  fi
-
-  ${ip} -f inet6 addr del ${old_ip6_address}/${old_ip6_prefixlen} \
-	dev ${interface}
-
-  exit_with_hooks 0
-fi
+
+    exit $exit_status
+}
+
+
+# Invoke the local dhcp client enter hooks, if they exist.
+run_hook /etc/dhclient-enter-hooks
+run_hookdir /etc/dhclient-enter-hooks.d
+
+# Execute the operation
+case "$reason" in
+
+    ### DHCPv4 Handlers
+
+    MEDIUM|ARPCHECK|ARPSEND)
+        # Do nothing
+        ;;
+    PREINIT)
+        # The DHCP client is requesting that an interface be
+        # configured as required in order to send packets prior to
+        # receiving an actual address. - dhclient-script(8)
+
+        # ensure interface is up
+        ${ip} link set dev ${interface} up
+
+        if [ -n "$alias_ip_address" ]; then
+            # flush alias IP from interface
+            ${ip} -4 addr flush dev ${interface} label ${interface}:0
+        fi
+
+        ;;
+
+    BOUND|RENEW|REBIND|REBOOT)
+        set_hostname
+
+        if [ -n "$old_ip_address" ] && [ -n "$alias_ip_address" ] &&
+           [ "$alias_ip_address" != "$old_ip_address" ]; then
+            # alias IP may have changed => flush it
+            ${ip} -4 addr flush dev ${interface} label ${interface}:0
+        fi
+
+        if [ -n "$old_ip_address" ] &&
+           [ "$old_ip_address" != "$new_ip_address" ]; then
+            # leased IP has changed => flush it
+            ${ip} -4 addr flush dev ${interface} label ${interface}
+        fi
+
+        if [ -z "$old_ip_address" ] ||
+           [ "$old_ip_address" != "$new_ip_address" ] ||
+           [ "$reason" = "BOUND" ] || [ "$reason" = "REBOOT" ]; then
+            # new IP has been leased or leased IP changed => set it
+            ${ip} -4 addr add ${new_ip_address}${new_subnet_mask:+/$new_subnet_mask} \
+                ${new_broadcast_address:+broadcast $new_broadcast_address} \
+                dev ${interface} label ${interface}
+
+            if [ -n "$new_interface_mtu" ]; then
+                # set MTU
+                ${ip} link set dev ${interface} mtu ${new_interface_mtu}
+            fi
+
+	    # if we have $new_rfc3442_classless_static_routes then we have to
+	    # ignore $new_routers entirely
+	    if [ ! "$new_rfc3442_classless_static_routes" ]; then
+		    # set if_metric if IF_METRIC is set or there's more than one router
+		    if_metric="$IF_METRIC"
+		    if [ "${new_routers%% *}" != "${new_routers}" ]; then
+			if_metric=${if_metric:-1}
+		    fi
+
+		    for router in $new_routers; do
+			if [ "$new_subnet_mask" = "255.255.255.255" ]; then
+			    # point-to-point connection => set explicit route
+			    ${ip} -4 route add ${router} dev $interface >/dev/null 2>&1
+			fi
+
+			# set default route
+			${ip} -4 route add default via ${router} dev ${interface} \
+			    ${if_metric:+metric $if_metric} >/dev/null 2>&1
+
+			if [ -n "$if_metric" ]; then
+			    if_metric=$((if_metric+1))
+			fi
+		    done
+	    fi
+        fi
+
+        if [ -n "$alias_ip_address" ] &&
+           [ "$new_ip_address" != "$alias_ip_address" ]; then
+            # separate alias IP given, which may have changed
+            # => flush it, set it & add host route to it
+            ${ip} -4 addr flush dev ${interface} label ${interface}:0
+            ${ip} -4 addr add ${alias_ip_address}${alias_subnet_mask:+/$alias_subnet_mask} \
+                dev ${interface} label ${interface}:0
+            ${ip} -4 route add ${alias_ip_address} dev ${interface} >/dev/null 2>&1
+        fi
+
+        # update /etc/resolv.conf
+        make_resolv_conf
+
+        ;;
+
+    EXPIRE|FAIL|RELEASE|STOP)
+        if [ -n "$alias_ip_address" ]; then
+            # flush alias IP
+            ${ip} -4 addr flush dev ${interface} label ${interface}:0
+        fi
+
+        if [ -n "$old_ip_address" ]; then
+            # flush leased IP
+            ${ip} -4 addr flush dev ${interface} label ${interface}
+        fi
+
+        if [ -n "$alias_ip_address" ]; then
+            # alias IP given => set it & add host route to it
+            ${ip} -4 addr add ${alias_ip_address}${alias_subnet_mask:+/$alias_subnet_mask} \
+                dev ${interface} label ${interface}:0
+            ${ip} -4 route add ${alias_ip_address} dev ${interface} >/dev/null 2>&1
+        fi
+
+        ;;
+
+    TIMEOUT)
+        if [ -n "$alias_ip_address" ]; then
+            # flush alias IP
+            ${ip} -4 addr flush dev ${interface} label ${interface}:0
+        fi
+
+        # set IP from recorded lease
+        ${ip} -4 addr add ${new_ip_address}${new_subnet_mask:+/$new_subnet_mask} \
+            ${new_broadcast_address:+broadcast $new_broadcast_address} \
+            dev ${interface} label ${interface}
+
+        if [ -n "$new_interface_mtu" ]; then
+            # set MTU
+            ${ip} link set dev ${interface} mtu ${new_interface_mtu}
+        fi
+
+        # if there is no router recorded in the lease or the 1st router answers pings
+        if [ -z "$new_routers" ] || ping -q -c 1 "${new_routers%% *}"; then
+	    # if we have $new_rfc3442_classless_static_routes then we have to
+	    # ignore $new_routers entirely
+	    if [ ! "$new_rfc3442_classless_static_routes" ]; then
+		    if [ -n "$alias_ip_address" ] &&
+		       [ "$new_ip_address" != "$alias_ip_address" ]; then
+			# separate alias IP given => set up the alias IP & add host route to it
+			${ip} -4 addr add \
+                              ${alias_ip_address}${alias_subnet_mask:+/$alias_subnet_mask} \
+			      dev ${interface} label ${interface}:0
+			${ip} -4 route add ${alias_ip_address} dev ${interface} >/dev/null 2>&1
+		    fi
+
+		    # set if_metric if IF_METRIC is set or there's more than one router
+		    if_metric="$IF_METRIC"
+		    if [ "${new_routers%% *}" != "${new_routers}" ]; then
+			if_metric=${if_metric:-1}
+		    fi
+
+		    # set default route
+		    for router in $new_routers; do
+			${ip} -4 route add default via ${router} dev ${interface} \
+			    ${if_metric:+metric $if_metric} >/dev/null 2>&1
+
+			if [ -n "$if_metric" ]; then
+			    if_metric=$((if_metric+1))
+			fi
+		    done
+	    fi
+
+            # update /etc/resolv.conf
+            make_resolv_conf
+        else
+            # flush all IPs from interface
+            ip -4 addr flush dev ${interface}
+            exit_with_hooks 2
+        fi
+
+        ;;
+
+    ### DHCPv6 Handlers
+    # TODO handle prefix change: ?based on ${old_ip6_prefix} and ${new_ip6_prefix}?
+
+    PREINIT6)
+        # ensure interface is up
+        ${ip} link set ${interface} up
+
+        # flush any stale global permanent IPs from interface
+        ${ip} -6 addr flush dev ${interface} scope global permanent
+
+        ;;
+
+    BOUND6|RENEW6|REBIND6)
+        if [ "${new_ip6_address}" ] && [ "${new_ip6_prefixlen}" ]; then
+            # set leased IP
+            ${ip} -6 addr add ${new_ip6_address}/${new_ip6_prefixlen} \
+                dev ${interface} scope global
+        fi
+
+        # update /etc/resolv.conf
+        if [ "${reason}" = BOUND6 ] ||
+           [ "${new_dhcp6_name_servers}" != "${old_dhcp6_name_servers}" ] ||
+           [ "${new_dhcp6_domain_search}" != "${old_dhcp6_domain_search}" ]; then
+            make_resolv_conf
+        fi
+
+        ;;
+
+    DEPREF6)
+        if [ -z "${cur_ip6_prefixlen}" ]; then
+            exit_with_hooks 2
+        fi
+
+        # set preferred lifetime of leased IP to 0
+        ${ip} -6 addr change ${cur_ip6_address}/${cur_ip6_prefixlen} \
+            dev ${interface} scope global preferred_lft 0
+
+        ;;
+
+    EXPIRE6|RELEASE6|STOP6)
+        if [ -z "${old_ip6_address}" ] || [ -z "${old_ip6_prefixlen}" ]; then
+            exit_with_hooks 2
+        fi
+
+        # delete leased IP
+        ${ip} -6 addr del ${old_ip6_address}/${old_ip6_prefixlen} \
+            dev ${interface}
+
+        ;;
+esac
 
 exit_with_hooks 0