[mirror_lxc.git] / hooks / dhclient-script

#!/bin/bash
# dhclient-script for Linux. Dan Halbert, March, 1997.
# Updated for Linux 2.[12] by Brian J. Murrell, January 1999.
# No guarantees about this. I'm a novice at the details of Linux
# networking.

# Notes:

# 0. This script is based on the netbsd script supplied with dhcp-970306.

# 1. ifconfig down apparently deletes all relevant routes and flushes
# the arp cache, so this doesn't need to be done explicitly.

# 2. The alias address handling here has not been tested AT ALL.
# I'm just going by the doc of modern Linux ip aliasing, which uses
# notations like eth0:0, eth0:1, for each alias.

# 3. I have to calculate the network address, and calculate the broadcast
# address if it is not supplied. This might be much more easily done
# by the dhclient C code, and passed on.

# 4. TIMEOUT not tested. ping has a flag I don't know, and I'm suspicious
# of the $1 in its args.

# 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.

# 6. LXC Fork
# Remove hooks and dependency on ifconfig.
# Resolve every paths against the $ROOTFS environment variable.

# 'ip' just looks too weird. Also, we now have unit-tests! Those unit-tests
# override 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() {
    local resolv_conf="${ROOTFS}/etc/resolv.conf"
    local new_resolv_conf="${ROOTFS}/etc/resolv.conf.dhclient-new"

    # DHCPv4
    if [ -n "$new_domain_search" ] || [ -n "$new_domain_name" ] ||
       [ -n "$new_domain_name_servers" ]; then
        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 $resolv_conf >>$new_resolv_conf
        fi

	if [ -f "$resolv_conf" ]; then
	    chown --reference=$resolv_conf $new_resolv_conf
	    chmod --reference=$resolv_conf $new_resolv_conf
	fi
        mv -f $new_resolv_conf $resolv_conf
    # DHCPv6
    elif [ -n "$new_dhcp6_domain_search" ] || [ -n "$new_dhcp6_name_servers" ]; then
        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 $resolv_conf >>$new_resolv_conf
        fi

	if [ -f "$resolv_conf" ]; then
            chown --reference=$resolv_conf $new_resolv_conf
            chmod --reference=$resolv_conf $new_resolv_conf
	fi
        mv -f $new_resolv_conf $resolv_conf
    fi
}

# 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
}

# 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 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

        # We need to give the kernel some time to active interface
        interface_up_wait_time=5
        for i in $(seq 0 ${interface_up_wait_time})
        do
            ${ip} addr show ${interface} | grep NO-CARRIER >/dev/null 2>&1
            if [ $? -ne 0 ]; then
                break;
            fi
            sleep 1
        done

        # flush any stale global permanent IPs from interface
        ${ip} -6 addr flush dev ${interface} scope global permanent

        # Wait for duplicate address detection for this interface if the
        # --dad-wait-time parameter has been specified and is greater than
        # zero.
        if [ ${dad_wait_time} -gt 0 ]; then
            # Check if any IPv6 address on this interface is marked as
            # tentative.
            ${ip} addr show ${interface} | grep inet6 | grep tentative \
                &> /dev/null
            if [ $? -eq 0 ]; then
                # Wait for duplicate address detection to complete or for
                # the timeout specified as --dad-wait-time.
                for i in $(seq 0 $dad_wait_time)
                do
                    # We're going to poll for the tentative flag every second.
                    sleep 1
                    ${ip} addr show ${interface} | grep inet6 | grep tentative \
                        &> /dev/null
                    if [ $? -ne 0 ]; then
                        break;
                    fi
                done
            fi
        fi

        ;;

    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 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 2
        fi

        # delete leased IP
        ${ip} -6 addr del ${old_ip6_address}/${old_ip6_prefixlen} \
            dev ${interface}

        ;;
esac

exit 0
Commit	Line	Data
27234deb JC	1	#!/bin/bash
	2	# dhclient-script for Linux. Dan Halbert, March, 1997.
	3	# Updated for Linux 2.[12] by Brian J. Murrell, January 1999.
	4	# No guarantees about this. I'm a novice at the details of Linux
	5	# networking.
	6
	7	# Notes:
	8
	9	# 0. This script is based on the netbsd script supplied with dhcp-970306.
	10
	11	# 1. ifconfig down apparently deletes all relevant routes and flushes
	12	# the arp cache, so this doesn't need to be done explicitly.
	13
	14	# 2. The alias address handling here has not been tested AT ALL.
	15	# I'm just going by the doc of modern Linux ip aliasing, which uses
	16	# notations like eth0:0, eth0:1, for each alias.
	17
	18	# 3. I have to calculate the network address, and calculate the broadcast
	19	# address if it is not supplied. This might be much more easily done
	20	# by the dhclient C code, and passed on.
	21
	22	# 4. TIMEOUT not tested. ping has a flag I don't know, and I'm suspicious
	23	# of the $1 in its args.
	24
	25	# 5. Script refresh in 2017. The aliasing code was too convoluted and needs
	26	# to go away. Migrated DHCPv4 script to ip command from iproute2 suite.
	27	# This is based on Debian script with some tweaks. ifconfig is no longer
	28	# used. Everything is done using ip tool from ip-route2.
	29
	30	# 6. LXC Fork
	31	# Remove hooks and dependency on ifconfig.
	32	# Resolve every paths against the $ROOTFS environment variable.
	33
	34	# 'ip' just looks too weird. Also, we now have unit-tests! Those unit-tests
768f183c	35	# override this line to use a fake ip-echo tool. It's also convenient
27234deb JC	36	# if your system holds ip tool in a non-standard location.
	37	ip=/sbin/ip
	38
	39	# update /etc/resolv.conf based on received values
	40	# This updated version mostly follows Debian script by Andrew Pollock et al.
	41	make_resolv_conf() {
	42	local resolv_conf="${ROOTFS}/etc/resolv.conf"
	43	local new_resolv_conf="${ROOTFS}/etc/resolv.conf.dhclient-new"
	44
	45	# DHCPv4
	46	if [ -n "$new_domain_search" ] \|\| [ -n "$new_domain_name" ] \|\|
	47	[ -n "$new_domain_name_servers" ]; then
	48	rm -f $new_resolv_conf
	49
	50	if [ -n "$new_domain_name" ]; then
	51	echo domain ${new_domain_name%% *} >>$new_resolv_conf
	52	fi
	53
	54	if [ -n "$new_domain_search" ]; then
	55	if [ -n "$new_domain_name" ]; then
	56	domain_in_search_list=""
	57	for domain in $new_domain_search; do
	58	if [ "$domain" = "${new_domain_name}" ] \|\|
	59	[ "$domain" = "${new_domain_name}." ]; then
	60	domain_in_search_list="Yes"
	61	fi
	62	done
	63	if [ -z "$domain_in_search_list" ]; then
	64	new_domain_search="$new_domain_name $new_domain_search"
	65	fi
	66	fi
	67	echo "search ${new_domain_search}" >> $new_resolv_conf
	68	elif [ -n "$new_domain_name" ]; then
	69	echo "search ${new_domain_name}" >> $new_resolv_conf
	70	fi
	71
	72	if [ -n "$new_domain_name_servers" ]; then
	73	for nameserver in $new_domain_name_servers; do
	74	echo nameserver $nameserver >>$new_resolv_conf
	75	done
	76	else # keep 'old' nameservers
	77	sed -n /^\w*[Nn][Aa][Mm][Ee][Ss][Ee][Rr][Vv][Ee][Rr]/p $resolv_conf >>$new_resolv_conf
	78	fi
	79
	80	if [ -f "$resolv_conf" ]; then
	81	chown --reference=$resolv_conf $new_resolv_conf
	82	chmod --reference=$resolv_conf $new_resolv_conf
	83	fi
	84	mv -f $new_resolv_conf $resolv_conf
	85	# DHCPv6
	86	elif [ -n "$new_dhcp6_domain_search" ] \|\| [ -n "$new_dhcp6_name_servers" ]; then
	87	rm -f $new_resolv_conf
	88
	89	if [ -n "$new_dhcp6_domain_search" ]; then
	90	echo "search ${new_dhcp6_domain_search}" >> $new_resolv_conf
	91	fi
	92
	93	if [ -n "$new_dhcp6_name_servers" ]; then
	94	for nameserver in $new_dhcp6_name_servers; do
	95	# append %interface to link-local-address nameservers
	96	if [ "${nameserver##fe80::}" != "$nameserver" ] \|\|
	97	[ "${nameserver##FE80::}" != "$nameserver" ]; then
	98	nameserver="${nameserver}%${interface}"
	99	fi
100	echo nameserver $nameserver >>$new_resolv_conf
101	done
102	else # keep 'old' nameservers
103	sed -n /^\w*[Nn][Aa][Mm][Ee][Ss][Ee][Rr][Vv][Ee][Rr]/p $resolv_conf >>$new_resolv_conf
104	fi
105
106	if [ -f "$resolv_conf" ]; then
107	chown --reference=$resolv_conf $new_resolv_conf
108	chmod --reference=$resolv_conf $new_resolv_conf
109	fi
110	mv -f $new_resolv_conf $resolv_conf
111	fi
112	}
113
114	# set host name
115	set_hostname() {
116	local current_hostname
117
118	if [ -n "$new_host_name" ]; then
119	current_hostname=$(hostname)
120
121	# current host name is empty, '(none)' or 'localhost' or differs from new one from DHCP
122	if [ -z "$current_hostname" ] \|\|
123	[ "$current_hostname" = '(none)' ] \|\|
124	[ "$current_hostname" = 'localhost' ] \|\|
125	[ "$current_hostname" = "$old_host_name" ]; then
126	if [ "$new_host_name" != "$old_host_name" ]; then
127	hostname "$new_host_name"
128	fi
129	fi
130	fi
131	}
132
133	# Execute the operation
134	case "$reason" in
135
136	### DHCPv4 Handlers
137
138	MEDIUM\|ARPCHECK\|ARPSEND)
139	# Do nothing
140	;;
141	PREINIT)
142	# The DHCP client is requesting that an interface be
143	# configured as required in order to send packets prior to
144	# receiving an actual address. - dhclient-script(8)
145
146	# ensure interface is up
147	${ip} link set dev ${interface} up
148
149	if [ -n "$alias_ip_address" ]; then
150	# flush alias IP from interface
151	${ip} -4 addr flush dev ${interface} label ${interface}:0
152	fi
153
154	;;
155
156	BOUND\|RENEW\|REBIND\|REBOOT)
157	set_hostname
158
159	if [ -n "$old_ip_address" ] && [ -n "$alias_ip_address" ] &&
160	[ "$alias_ip_address" != "$old_ip_address" ]; then
161	# alias IP may have changed => flush it
162	${ip} -4 addr flush dev ${interface} label ${interface}:0
163	fi
164
165	if [ -n "$old_ip_address" ] &&
166	[ "$old_ip_address" != "$new_ip_address" ]; then
167	# leased IP has changed => flush it
168	${ip} -4 addr flush dev ${interface} label ${interface}
169	fi
170
171	if [ -z "$old_ip_address" ] \|\|
172	[ "$old_ip_address" != "$new_ip_address" ] \|\|
173	[ "$reason" = "BOUND" ] \|\| [ "$reason" = "REBOOT" ]; then
174	# new IP has been leased or leased IP changed => set it
175	${ip} -4 addr add ${new_ip_address}${new_subnet_mask:+/$new_subnet_mask} \
176	${new_broadcast_address:+broadcast $new_broadcast_address} \
177	dev ${interface} label ${interface}
178
179	if [ -n "$new_interface_mtu" ]; then
180	# set MTU
181	${ip} link set dev ${interface} mtu ${new_interface_mtu}
182	fi
183
184	# if we have $new_rfc3442_classless_static_routes then we have to
185	# ignore $new_routers entirely
186	if [ ! "$new_rfc3442_classless_static_routes" ]; then
187	# set if_metric if IF_METRIC is set or there's more than one router
188	if_metric="$IF_METRIC"
189	if [ "${new_routers%% *}" != "${new_routers}" ]; then
190	if_metric=${if_metric:-1}
191	fi
192
193	for router in $new_routers; do
194	if [ "$new_subnet_mask" = "255.255.255.255" ]; then
195	# point-to-point connection => set explicit route
196	${ip} -4 route add ${router} dev $interface >/dev/null 2>&1
197	fi
198
199	# set default route
200	${ip} -4 route add default via ${router} dev ${interface} \
201	${if_metric:+metric $if_metric} >/dev/null 2>&1
202
203	if [ -n "$if_metric" ]; then
204	if_metric=$((if_metric+1))
205	fi
206	done
207	fi
208	fi
209
210	if [ -n "$alias_ip_address" ] &&
211	[ "$new_ip_address" != "$alias_ip_address" ]; then
212	# separate alias IP given, which may have changed
213	# => flush it, set it & add host route to it
214	${ip} -4 addr flush dev ${interface} label ${interface}:0
215	${ip} -4 addr add ${alias_ip_address}${alias_subnet_mask:+/$alias_subnet_mask} \
216	dev ${interface} label ${interface}:0
217	${ip} -4 route add ${alias_ip_address} dev ${interface} >/dev/null 2>&1
218	fi
219
220	# update /etc/resolv.conf
221	make_resolv_conf
222
223	;;
224
225	EXPIRE\|FAIL\|RELEASE\|STOP)
226	if [ -n "$alias_ip_address" ]; then
227	# flush alias IP
228	${ip} -4 addr flush dev ${interface} label ${interface}:0
229	fi
230
231	if [ -n "$old_ip_address" ]; then
232	# flush leased IP
233	${ip} -4 addr flush dev ${interface} label ${interface}
234	fi
235
236	if [ -n "$alias_ip_address" ]; then
237	# alias IP given => set it & add host route to it
238	${ip} -4 addr add ${alias_ip_address}${alias_subnet_mask:+/$alias_subnet_mask} \
239	dev ${interface} label ${interface}:0
240	${ip} -4 route add ${alias_ip_address} dev ${interface} >/dev/null 2>&1
241	fi
242
243	;;
244
245	TIMEOUT)
246	if [ -n "$alias_ip_address" ]; then
247	# flush alias IP
248	${ip} -4 addr flush dev ${interface} label ${interface}:0
249	fi
250
251	# set IP from recorded lease
252	${ip} -4 addr add ${new_ip_address}${new_subnet_mask:+/$new_subnet_mask} \
253	${new_broadcast_address:+broadcast $new_broadcast_address} \
254	dev ${interface} label ${interface}
255
256	if [ -n "$new_interface_mtu" ]; then
257	# set MTU
258	${ip} link set dev ${interface} mtu ${new_interface_mtu}
259	fi
260
261	# if there is no router recorded in the lease or the 1st router answers pings
262	if [ -z "$new_routers" ] \|\| ping -q -c 1 "${new_routers%% *}"; then
263	# if we have $new_rfc3442_classless_static_routes then we have to
264	# ignore $new_routers entirely
265	if [ ! "$new_rfc3442_classless_static_routes" ]; then
266	if [ -n "$alias_ip_address" ] &&
267	[ "$new_ip_address" != "$alias_ip_address" ]; then
268	# separate alias IP given => set up the alias IP & add host route to it
269	${ip} -4 addr add \
270	${alias_ip_address}${alias_subnet_mask:+/$alias_subnet_mask} \
271	dev ${interface} label ${interface}:0
272	${ip} -4 route add ${alias_ip_address} dev ${interface} >/dev/null 2>&1
273	fi
274
275	# set if_metric if IF_METRIC is set or there's more than one router
276	if_metric="$IF_METRIC"
277	if [ "${new_routers%% *}" != "${new_routers}" ]; then
278	if_metric=${if_metric:-1}
279	fi
280
281	# set default route
282	for router in $new_routers; do
283	${ip} -4 route add default via ${router} dev ${interface} \
284	${if_metric:+metric $if_metric} >/dev/null 2>&1
285
286	if [ -n "$if_metric" ]; then
287	if_metric=$((if_metric+1))
288	fi
289	done
290	fi
291
292	# update /etc/resolv.conf
293	make_resolv_conf
294	else
295	# flush all IPs from interface
296	${ip} -4 addr flush dev ${interface}
297	exit 2
298	fi
299
300	;;
301
302	### DHCPv6 Handlers
303	# TODO handle prefix change: ?based on ${old_ip6_prefix} and ${new_ip6_prefix}?
304
305	PREINIT6)
306	# ensure interface is up
307	${ip} link set ${interface} up
308
309	# We need to give the kernel some time to active interface
310	interface_up_wait_time=5
311	for i in $(seq 0 ${interface_up_wait_time})
312	do
313	${ip} addr show ${interface} \| grep NO-CARRIER >/dev/null 2>&1
314	if [ $? -ne 0 ]; then
315	break;
316	fi
317	sleep 1
318	done
319
320	# flush any stale global permanent IPs from interface
321	${ip} -6 addr flush dev ${interface} scope global permanent
322
323	# Wait for duplicate address detection for this interface if the
324	# --dad-wait-time parameter has been specified and is greater than
325	# zero.
326	if [ ${dad_wait_time} -gt 0 ]; then
327	# Check if any IPv6 address on this interface is marked as
328	# tentative.
329	${ip} addr show ${interface} \| grep inet6 \| grep tentative \
330	&> /dev/null
331	if [ $? -eq 0 ]; then
332	# Wait for duplicate address detection to complete or for
333	# the timeout specified as --dad-wait-time.
334	for i in $(seq 0 $dad_wait_time)
335	do
336	# We're going to poll for the tentative flag every second.
337	sleep 1
338	${ip} addr show ${interface} \| grep inet6 \| grep tentative \
339	&> /dev/null
340	if [ $? -ne 0 ]; then
341	break;
342	fi
343	done
344	fi
345	fi
346
347	;;
348
349	BOUND6\|RENEW6\|REBIND6)
350	if [ "${new_ip6_address}" ] && [ "${new_ip6_prefixlen}" ]; then
351	# set leased IP
352	${ip} -6 addr add ${new_ip6_address}/${new_ip6_prefixlen} \
353	dev ${interface} scope global
354	fi
355
356	# update /etc/resolv.conf
357	if [ "${reason}" = BOUND6 ] \|\|
358	[ "${new_dhcp6_name_servers}" != "${old_dhcp6_name_servers}" ] \|\|
359	[ "${new_dhcp6_domain_search}" != "${old_dhcp6_domain_search}" ]; then
360	make_resolv_conf
361	fi
362
363	;;
364
365	DEPREF6)
366	if [ -z "${cur_ip6_prefixlen}" ]; then
367	exit 2
368	fi
369
370	# set preferred lifetime of leased IP to 0
371	${ip} -6 addr change ${cur_ip6_address}/${cur_ip6_prefixlen} \
372	dev ${interface} scope global preferred_lft 0
373
374	;;
375
376	EXPIRE6\|RELEASE6\|STOP6)
377	if [ -z "${old_ip6_address}" ] \|\| [ -z "${old_ip6_prefixlen}" ]; then
378	exit 2
379	fi
380
381	# delete leased IP
382	${ip} -6 addr del ${old_ip6_address}/${old_ip6_prefixlen} \
383	dev ${interface}
384
385	;;
386	esac
387
388	exit 0