Submitted By: DJ Lucas (dj at linuxfromscratch dot org)
Date: 2005-06-18
Initial Package Version: 3.0.2
Origin: Jim Gifford, Bruce Dubbs, DJ Lucas
Description: Fixes client script to use iproute2 (added flush to previous 
             unversioned patches)
Upstream Status:  Not submitted

--- dhcp-3.0.2-orig/client/scripts/linux	2002-11-14 19:09:09.000000000 -0600
+++ dhcp-3.0.2/client/scripts/linux	2005-06-18 22:54:59.000000000 -0500
@@ -1,26 +1,15 @@
 #!/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.
+
+# Updated to iproute2 by Jim Gifford (scripts@jg555.com)
 
 # 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.
+# 1. This script was modified to work with iproute2
+# 2. cidr_convert based on a script by Kevin Fleming (kpfleming@linuxfromscratch.org)
+# 3. Updated to delete addresses when taking an interface down (bdubbs@linuxfromscratch.org)
 
 make_resolv_conf() {
   if [ "x$new_domain_name" != x ] && [ x"$new_domain_name_servers" != x ]; then
@@ -32,6 +21,30 @@
   fi
 }
 
+dec2binary()
+{
+    local n=$1
+    local ret=""
+    while [ $n != 0 ]; do
+        ret=$[$n%2]$ret
+        n=$[$n>>1]
+    done
+    echo $ret
+}
+
+mask_to_binary()
+{
+    echo `dec2binary $1``dec2binary $2``dec2binary $3``dec2binary $4`
+}
+
+cidr_convert()
+{
+	netmask=$1
+        local mask=`mask_to_binary ${netmask//./ }`
+        mask=${mask%%0*}
+        cidr=${#mask}
+}
+
 # Must be used on exit.   Invokes the local dhcp client exit hooks, if any.
 exit_with_hooks() {
   exit_status=$1
@@ -53,11 +66,6 @@
   fi
 fi
 
-release=`uname -r`
-release=`expr $release : '\(.*\)\..*'`
-relminor=`echo $release |sed -e 's/[0-9]*\.\([0-9][0-9]*\)\(\..*\)*$/\1/'`
-relmajor=`echo $release |sed -e 's/\([0-9][0-9]*\)\..*$/\1/'`
-
 if [ x$new_broadcast_address != x ]; then
   new_broadcast_arg="broadcast $new_broadcast_address"
 fi
@@ -65,13 +73,12 @@
   old_broadcast_arg="broadcast $old_broadcast_address"
 fi
 if [ x$new_subnet_mask != x ]; then
-  new_subnet_arg="netmask $new_subnet_mask"
+  cidr_convert $new_subnet_mask
+  new_subnet_arg="$cidr"
 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"
+  cidr_convert $old_subnet_mask
+  old_subnet_arg="$cidr"
 fi
 
 if [ x$reason = xMEDIUM ]; then
@@ -82,17 +89,10 @@
 if [ x$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
-  if [ $relmajor -lt 2 ] || ( [ $relmajor -eq 2 ] && [ $relminor -eq 0 ] )
-   then
-    ifconfig $interface inet 0.0.0.0 netmask 0.0.0.0 \
-		broadcast 255.255.255.255 up
-    # Add route to make broadcast work. Do not omit netmask.
-    route add default dev $interface netmask 0.0.0.0
-  else
-    ifconfig $interface 0 up
+    ip link set $interface down
+    ip addr del $alias_ip_address  dev $interface
   fi
+  ip link set $interface up
 
   # We need to give the kernel some time to get the interface up.
   sleep 1
@@ -115,83 +115,51 @@
     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,
+    # IP address changed. Bring down the interface, delete all routes,
     # and clear the ARP cache.
-    ifconfig $interface inet 0 down
-
+    ip link set $interface down
+    ip addr flush dev $interface
   fi
   if [ x$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
+    ip link set $interface up
+    ip addr add $new_ip_address/$new_subnet_arg $new_broadcast_arg \
+       label $interface dev $interface
     # Add a network route to the computed network address.
-    if [ $relmajor -lt 2 ] || \
-		( [ $relmajor -eq 2 ] && [ $relminor -eq 0 ] ); then
-      route add -net $new_network_number $new_subnet_arg dev $interface
-    fi
     for router in $new_routers; do
-      route add default gw $router
+      ip route add default via $router
     done
   fi
-  if [ x$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
+    # Shut down interface, delete routes, and clear arp cache.
+    ip link set $interface down
+    ip addr flush dev $interface
   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
+  ip link set $interface up
+  ip addr set $new_ip_address/$new_subnet_arg $new_broadcast_arg \
+     label $interface dev $interface
   set $new_routers
-  ############## what is -w in ping?
-  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
-    fi
-    if [ $relmajor -lt 2 ] || \
-		( [ $relmajor -eq 2 ] && [ $relminor -eq 0 ] ); then
-      route add -net $new_network_number
-    fi
-    for router in $new_routers; do
-      route add default gw $router
-    done
-    make_resolv_conf
-    exit_with_hooks 0
-  fi
-  ifconfig $interface inet 0 down
+  
+  for router in $new_routers; do
+    ip route add default via $router
+  done
+  
+  make_resolv_conf
+  exit_with_hooks 0
+  ip link set $interface down
+  ip addr flush dev $interface
   exit_with_hooks 1
 fi