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For linux scripts the deprected ifconfig has been replaced with ip. However there is one leftover, replace that as well. Closes #77 Signed-off-by: Christian Hesse <mail@eworm.de>
497 lines
16 KiB
Bash
Executable File
497 lines
16 KiB
Bash
Executable File
#!/bin/bash
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# dhclient-script for Linux. Dan Halbert, March, 1997.
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# Updated for Linux 2.[12] by Brian J. Murrell, January 1999.
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# No guarantees about this. I'm a novice at the details of Linux
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# networking.
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# Notes:
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# 0. This script is based on the netbsd script supplied with dhcp-970306.
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# 1. ifconfig down apparently deletes all relevant routes and flushes
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# the arp cache, so this doesn't need to be done explicitly.
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# 2. The alias address handling here has not been tested AT ALL.
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# I'm just going by the doc of modern Linux ip aliasing, which uses
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# notations like eth0:0, eth0:1, for each alias.
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# 3. I have to calculate the network address, and calculate the broadcast
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# address if it is not supplied. This might be much more easily done
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# by the dhclient C code, and passed on.
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# 4. TIMEOUT not tested. ping has a flag I don't know, and I'm suspicious
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# of the $1 in its args.
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# 5. Script refresh in 2017. The aliasing code was too convoluted and needs
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# to go away. Migrated DHCPv4 script to ip command from iproute2 suite.
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# This is based on Debian script with some tweaks. ifconfig is no longer
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# used. Everything is done using ip tool from ip-route2.
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# 'ip' just looks too weird. Also, we now have unit-tests! Those unit-tests
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# overwirte this line to use a fake ip-echo tool. It's also convenient
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# if your system holds ip tool in a non-standard location.
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ip=/sbin/ip
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# update /etc/resolv.conf based on received values
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# This updated version mostly follows Debian script by Andrew Pollock et al.
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make_resolv_conf() {
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local new_resolv_conf
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# DHCPv4
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if [ -n "$new_domain_search" ] || [ -n "$new_domain_name" ] ||
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[ -n "$new_domain_name_servers" ]; then
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new_resolv_conf=/etc/resolv.conf.dhclient-new
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rm -f $new_resolv_conf
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if [ -n "$new_domain_name" ]; then
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echo domain ${new_domain_name%% *} >>$new_resolv_conf
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fi
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if [ -n "$new_domain_search" ]; then
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if [ -n "$new_domain_name" ]; then
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domain_in_search_list=""
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for domain in $new_domain_search; do
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if [ "$domain" = "${new_domain_name}" ] ||
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[ "$domain" = "${new_domain_name}." ]; then
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domain_in_search_list="Yes"
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fi
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done
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if [ -z "$domain_in_search_list" ]; then
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new_domain_search="$new_domain_name $new_domain_search"
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fi
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fi
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echo "search ${new_domain_search}" >> $new_resolv_conf
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elif [ -n "$new_domain_name" ]; then
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echo "search ${new_domain_name}" >> $new_resolv_conf
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fi
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if [ -n "$new_domain_name_servers" ]; then
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for nameserver in $new_domain_name_servers; do
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echo nameserver $nameserver >>$new_resolv_conf
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done
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else # keep 'old' nameservers
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sed -n /^\w*[Nn][Aa][Mm][Ee][Ss][Ee][Rr][Vv][Ee][Rr]/p /etc/resolv.conf >>$new_resolv_conf
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fi
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if [ -f /etc/resolv.conf ]; then
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chown --reference=/etc/resolv.conf $new_resolv_conf
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chmod --reference=/etc/resolv.conf $new_resolv_conf
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fi
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mv -f $new_resolv_conf /etc/resolv.conf
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# DHCPv6
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elif [ -n "$new_dhcp6_domain_search" ] || [ -n "$new_dhcp6_name_servers" ]; then
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new_resolv_conf=/etc/resolv.conf.dhclient-new
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rm -f $new_resolv_conf
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if [ -n "$new_dhcp6_domain_search" ]; then
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echo "search ${new_dhcp6_domain_search}" >> $new_resolv_conf
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fi
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if [ -n "$new_dhcp6_name_servers" ]; then
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for nameserver in $new_dhcp6_name_servers; do
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# append %interface to link-local-address nameservers
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if [ "${nameserver##fe80::}" != "$nameserver" ] ||
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[ "${nameserver##FE80::}" != "$nameserver" ]; then
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nameserver="${nameserver}%${interface}"
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fi
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echo nameserver $nameserver >>$new_resolv_conf
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done
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else # keep 'old' nameservers
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sed -n /^\w*[Nn][Aa][Mm][Ee][Ss][Ee][Rr][Vv][Ee][Rr]/p /etc/resolv.conf >>$new_resolv_conf
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fi
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if [ -f /etc/resolv.conf ]; then
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chown --reference=/etc/resolv.conf $new_resolv_conf
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chmod --reference=/etc/resolv.conf $new_resolv_conf
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fi
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mv -f $new_resolv_conf /etc/resolv.conf
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fi
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}
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# set host name
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set_hostname() {
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local current_hostname
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if [ -n "$new_host_name" ]; then
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current_hostname=$(hostname)
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# current host name is empty, '(none)' or 'localhost' or differs from new one from DHCP
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if [ -z "$current_hostname" ] ||
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[ "$current_hostname" = '(none)' ] ||
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[ "$current_hostname" = 'localhost' ] ||
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[ "$current_hostname" = "$old_host_name" ]; then
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if [ "$new_host_name" != "$old_host_name" ]; then
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hostname "$new_host_name"
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fi
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fi
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fi
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}
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# run given script
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run_hook() {
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local script
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local exit_status
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script="$1"
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if [ -f $script ]; then
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. $script
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fi
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if [ -n "$exit_status" ] && [ "$exit_status" -ne 0 ]; then
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logger -p daemon.err "$script returned non-zero exit status $exit_status"
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fi
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return $exit_status
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}
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# run scripts in given directory
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run_hookdir() {
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local dir
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local exit_status
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dir="$1"
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if [ -d "$dir" ]; then
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for script in $(run-parts --list $dir); do
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run_hook $script || true
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exit_status=$?
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done
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fi
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return $exit_status
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}
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# Must be used on exit. Invokes the local dhcp client exit hooks, if any.
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exit_with_hooks() {
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exit_status=$1
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# Source the documented exit-hook script, if it exists
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if ! run_hook /etc/dhclient-exit-hooks; then
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exit_status=$?
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fi
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# Now run scripts in the Debian-specific directory.
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if ! run_hookdir /etc/dhclient-exit-hooks.d; then
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exit_status=$?
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fi
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exit $exit_status
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}
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# This function was largely borrowed from dhclient-script that
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# ships with Centos, authored by Jiri Popelka and David Cantrell
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# of Redhat. Thanks guys.
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add_ipv6_addr_with_DAD() {
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${ip} -6 addr replace ${new_ip6_address}/${new_ip6_prefixlen} \
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dev ${interface} scope global valid_lft ${new_max_life} \
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preferred_lft ${new_preferred_life}
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if [ ${dad_wait_time} -le 0 ]
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then
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# if we're not waiting for DAD, assume we're good
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return 0
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fi
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# Repeatedly test whether newly added address passed
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# duplicate address detection (DAD)
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for i in $(seq 1 ${dad_wait_time}); do
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sleep 1 # give the DAD some time
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addr=$(${ip} -6 addr show dev ${interface} \
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| grep ${new_ip6_address}/${new_ip6_prefixlen})
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# tentative flag == DAD is still not complete
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tentative=$(echo "${addr}" | grep tentative)
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# dadfailed flag == address is already in use somewhere else
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dadfailed=$(echo "${addr}" | grep dadfailed)
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if [ -n "${dadfailed}" ] ; then
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# address was added with valid_lft/preferred_lft 'forever',
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# remove it
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${ip} -6 addr del ${new_ip6_address}/${new_ip6_prefixlen} \
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dev ${interface}
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exit_with_hooks 3
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fi
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if [ -z "${tentative}" ] ; then
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if [ -n "${addr}" ]; then
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# DAD is over
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return 0
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else
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# address was auto-removed (or not added at all)
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exit_with_hooks 3
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fi
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fi
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done
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return 0
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}
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# Invoke the local dhcp client enter hooks, if they exist.
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run_hook /etc/dhclient-enter-hooks
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run_hookdir /etc/dhclient-enter-hooks.d
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# Execute the operation
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case "$reason" in
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### DHCPv4 Handlers
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MEDIUM|ARPCHECK|ARPSEND)
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# Do nothing
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;;
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PREINIT)
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# The DHCP client is requesting that an interface be
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# configured as required in order to send packets prior to
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# receiving an actual address. - dhclient-script(8)
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# ensure interface is up
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${ip} link set dev ${interface} up
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if [ -n "$alias_ip_address" ]; then
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# flush alias IP from interface
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${ip} -4 addr flush dev ${interface} label ${interface}:0
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fi
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;;
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BOUND|RENEW|REBIND|REBOOT)
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set_hostname
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if [ -n "$old_ip_address" ] && [ -n "$alias_ip_address" ] &&
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[ "$alias_ip_address" != "$old_ip_address" ]; then
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# alias IP may have changed => flush it
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${ip} -4 addr flush dev ${interface} label ${interface}:0
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fi
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if [ -n "$old_ip_address" ] &&
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[ "$old_ip_address" != "$new_ip_address" ]; then
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# leased IP has changed => flush it
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${ip} -4 addr flush dev ${interface} label ${interface}
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fi
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if [ -z "$old_ip_address" ] ||
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[ "$old_ip_address" != "$new_ip_address" ] ||
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[ "$reason" = "BOUND" ] || [ "$reason" = "REBOOT" ]; then
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# new IP has been leased or leased IP changed => set it
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${ip} -4 addr add ${new_ip_address}${new_subnet_mask:+/$new_subnet_mask} \
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${new_broadcast_address:+broadcast $new_broadcast_address} \
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dev ${interface} label ${interface}
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if [ -n "$new_interface_mtu" ]; then
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# set MTU
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${ip} link set dev ${interface} mtu ${new_interface_mtu}
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fi
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# if we have $new_rfc3442_classless_static_routes then we have to
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# ignore $new_routers entirely
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if [ ! "$new_rfc3442_classless_static_routes" ]; then
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# set if_metric if IF_METRIC is set or there's more than one router
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if_metric="$IF_METRIC"
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if [ "${new_routers%% *}" != "${new_routers}" ]; then
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if_metric=${if_metric:-1}
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fi
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for router in $new_routers; do
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if [ "$new_subnet_mask" = "255.255.255.255" ]; then
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# point-to-point connection => set explicit route
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${ip} -4 route add ${router} dev $interface >/dev/null 2>&1
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fi
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# set default route
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${ip} -4 route add default via ${router} dev ${interface} \
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${if_metric:+metric $if_metric} >/dev/null 2>&1
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if [ -n "$if_metric" ]; then
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if_metric=$((if_metric+1))
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fi
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done
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fi
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fi
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if [ -n "$alias_ip_address" ] &&
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[ "$new_ip_address" != "$alias_ip_address" ]; then
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# separate alias IP given, which may have changed
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# => flush it, set it & add host route to it
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${ip} -4 addr flush dev ${interface} label ${interface}:0
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${ip} -4 addr add ${alias_ip_address}${alias_subnet_mask:+/$alias_subnet_mask} \
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dev ${interface} label ${interface}:0
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${ip} -4 route add ${alias_ip_address} dev ${interface} >/dev/null 2>&1
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fi
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# update /etc/resolv.conf
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make_resolv_conf
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;;
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EXPIRE|FAIL|RELEASE|STOP)
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if [ -n "$alias_ip_address" ]; then
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# flush alias IP
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${ip} -4 addr flush dev ${interface} label ${interface}:0
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fi
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if [ -n "$old_ip_address" ]; then
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# flush leased IP
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${ip} -4 addr flush dev ${interface} label ${interface}
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fi
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if [ -n "$alias_ip_address" ]; then
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# alias IP given => set it & add host route to it
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${ip} -4 addr add ${alias_ip_address}${alias_subnet_mask:+/$alias_subnet_mask} \
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dev ${interface} label ${interface}:0
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${ip} -4 route add ${alias_ip_address} dev ${interface} >/dev/null 2>&1
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fi
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;;
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TIMEOUT)
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if [ -n "$alias_ip_address" ]; then
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# flush alias IP
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${ip} -4 addr flush dev ${interface} label ${interface}:0
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fi
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# set IP from recorded lease
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${ip} -4 addr add ${new_ip_address}${new_subnet_mask:+/$new_subnet_mask} \
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${new_broadcast_address:+broadcast $new_broadcast_address} \
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dev ${interface} label ${interface}
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if [ -n "$new_interface_mtu" ]; then
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# set MTU
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${ip} link set dev ${interface} mtu ${new_interface_mtu}
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fi
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# if there is no router recorded in the lease or the 1st router answers pings
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if [ -z "$new_routers" ] || ping -q -c 1 "${new_routers%% *}"; then
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# if we have $new_rfc3442_classless_static_routes then we have to
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# ignore $new_routers entirely
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if [ ! "$new_rfc3442_classless_static_routes" ]; then
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if [ -n "$alias_ip_address" ] &&
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[ "$new_ip_address" != "$alias_ip_address" ]; then
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# separate alias IP given => set up the alias IP & add host route to it
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${ip} -4 addr add \
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${alias_ip_address}${alias_subnet_mask:+/$alias_subnet_mask} \
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dev ${interface} label ${interface}:0
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${ip} -4 route add ${alias_ip_address} dev ${interface} >/dev/null 2>&1
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fi
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# set if_metric if IF_METRIC is set or there's more than one router
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if_metric="$IF_METRIC"
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if [ "${new_routers%% *}" != "${new_routers}" ]; then
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if_metric=${if_metric:-1}
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fi
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# set default route
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for router in $new_routers; do
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${ip} -4 route add default via ${router} dev ${interface} \
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${if_metric:+metric $if_metric} >/dev/null 2>&1
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if [ -n "$if_metric" ]; then
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if_metric=$((if_metric+1))
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fi
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done
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fi
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# update /etc/resolv.conf
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make_resolv_conf
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else
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# flush all IPs from interface
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ip -4 addr flush dev ${interface}
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exit_with_hooks 2
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fi
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;;
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V6ONLY)
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if [ -n "$old_ip_address" ]; then
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# flush leased IP
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${ip} -4 addr flush dev ${interface} label ${interface}
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fi
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;;
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### DHCPv6 Handlers
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# TODO handle prefix change: ?based on ${old_ip6_prefix} and ${new_ip6_prefix}?
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PREINIT6)
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# ensure interface is up
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${ip} link set ${interface} up
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# We need to give the kernel some time to active interface
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interface_up_wait_time=5
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for i in $(seq 0 ${interface_up_wait_time})
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do
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${ip} link show dev ${interface} | grep -q LOWER_UP 2>&1
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if [ $? -eq 0 ]; then
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break;
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fi
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sleep 1
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done
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# flush any stale global permanent IPs from interface
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${ip} -6 addr flush dev ${interface} scope global permanent
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# Wait for duplicate address detection for this interface if the
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# --dad-wait-time parameter has been specified and is greater than
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# zero.
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if [ ${dad_wait_time} -gt 0 ]; then
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# Check if any IPv6 address on this interface is marked as
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# tentative.
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${ip} addr show ${interface} | grep inet6 | grep tentative \
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&> /dev/null
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if [ $? -eq 0 ]; then
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# Wait for duplicate address detection to complete or for
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# the timeout specified as --dad-wait-time.
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for i in $(seq 0 $dad_wait_time)
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do
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# We're going to poll for the tentative flag every second.
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sleep 1
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${ip} addr show ${interface} | grep inet6 | grep tentative \
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&> /dev/null
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if [ $? -ne 0 ]; then
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break;
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fi
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done
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fi
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fi
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;;
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BOUND6|RENEW6|REBIND6)
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if [ "${new_ip6_address}" ] && [ "${new_ip6_prefixlen}" ]; then
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# set leased IP
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add_ipv6_addr_with_DAD
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fi
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# update /etc/resolv.conf
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if [ "${reason}" = BOUND6 ] ||
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[ "${new_dhcp6_name_servers}" != "${old_dhcp6_name_servers}" ] ||
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[ "${new_dhcp6_domain_search}" != "${old_dhcp6_domain_search}" ]; then
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make_resolv_conf
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fi
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;;
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DEPREF6)
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if [ -z "${cur_ip6_prefixlen}" ]; then
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exit_with_hooks 2
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fi
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# set preferred lifetime of leased IP to 0
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${ip} -6 addr change ${cur_ip6_address}/${cur_ip6_prefixlen} \
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dev ${interface} scope global preferred_lft 0
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;;
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EXPIRE6|RELEASE6|STOP6)
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if [ -z "${old_ip6_address}" ] || [ -z "${old_ip6_prefixlen}" ]; then
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exit_with_hooks 2
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fi
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# delete leased IP
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${ip} -6 addr del ${old_ip6_address}/${old_ip6_prefixlen} \
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dev ${interface}
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;;
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esac
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exit_with_hooks 0
|