diff options
Diffstat (limited to 'recipes-connectivity/dhcp/files/dhclient-exit-hooks')
| -rw-r--r-- | recipes-connectivity/dhcp/files/dhclient-exit-hooks | 92 |
1 files changed, 92 insertions, 0 deletions
diff --git a/recipes-connectivity/dhcp/files/dhclient-exit-hooks b/recipes-connectivity/dhcp/files/dhclient-exit-hooks new file mode 100644 index 00000000..3be5e024 --- /dev/null +++ b/recipes-connectivity/dhcp/files/dhclient-exit-hooks @@ -0,0 +1,92 @@ +#!/bin/bash +# +# /etc/dhcp/dhclient-exit-hooks +# +# This file is sourced by /sbin/dhclient-script. +# +# dhcp option 121 is defined in RFC3442. The following is the link. +# http://www.ietf.org/rfc/rfc3442.txt +# +# The code for this option is 121, and its minimum length is 5 bytes. +# This option can contain one or more static routes, each of which +# consists of a destination descriptor and the IP address of the router +# that should be used to reach that destination. +# +# Code Len Destination 1 Router 1 +# +-----+---+----+-----+----+----+----+----+----+ +# | 121 | n | d1 | ... | dN | r1 | r2 | r3 | r4 | +# +-----+---+----+-----+----+----+----+----+----+ +# +# Destination 2 Router 2 +# +----+-----+----+----+----+----+----+ +# | d1 | ... | dN | r1 | r2 | r3 | r4 | +# +----+-----+----+----+----+----+----+ +# +# In the above example, two static routes are specified. +# +# The following table contains some examples of how various subnet +# number/mask combinations can be encoded: +# +# Subnet number Subnet mask Destination descriptor +# 0 0 0 +# 10.0.0.0 255.0.0.0 8.10 +# 10.0.0.0 255.255.255.0 24.10.0.0 +# 10.17.0.0 255.255.0.0 16.10.17 +# 10.27.129.0 255.255.255.0 24.10.27.129 +# 10.229.0.128 255.255.255.128 25.10.229.0.128 +# 10.198.122.47 255.255.255.255 32.10.198.122.47 +# +# For metadata service, the following is a valid route from nova-api that +# the VM instance can uses to retrieve metadata. +# +# 32 169 254 169 254 128 224 149 201 +# +# In the above example, mask length of destination descriptor is always 32, +# destination is always "169.254.169.254", and the gateway is a valid IP address. +# +# The add_routes function takes an array of unsigned integer 8, separated by spaces, +# parse them, and added each of the routes into routing table. +# + +function add_routes() { +while [ $# -ne 0 ]; do + mask=$1 + shift + + # Parse the arguments into a CIDR net/mask string + if [ $mask -eq 32 ]; then + destination="-host $1.$2.$3.$4" + shift; shift; shift; shift + elif [ $mask -gt 24 ]; then + destination="-net $1.$2.$3.$4/$mask" + shift; shift; shift; shift + elif [ $mask -gt 16 ]; then + destination="-net $1.$2.$3.0/$mask" + shift; shift; shift + elif [ $mask -gt 8 ]; then + destination="-net $1.$2.0.0/$mask" + shift; shift + else + destination="-net $1.0.0.0/$mask" + shift + fi + + # Read the gateway + gateway="$1.$2.$3.$4" + shift; shift; shift; shift + + # Add route into routing table + route add $destination gw $gateway + + # Print it out if the route is added successfully + if [ $? = 0 ]; then + echo "Added route \"$destination gw $gateway\"" + fi +done +} + +# Call add_routes to add routes +if [ "x$new_classless_static_routes" != x ]; then + add_routes $new_classless_static_routes +fi + |