#!/usr/bin/env ruby
# == Synopsis
#
# configure-network-interfaces: configures /etc/network/intefaces using information from lshw
#
# == Usage
#
# configure-network-interfaces [OPTIONS]
#
# configure-network-interfaces --bridge \
# --ip br0,10.0.0.1,255.0.0.0,10.10.0.2 \
# --ip br1,192.168.0.200,255.255.255.0,192.168.0.1 \
# --interfaces-file /etc/network/interfaces
#
# Configures 2 interfaces as bridges with the static IPs provided
#
# --debug, -D:
# enable debug mode
#
# --dry-run, -n:
# do not actually write the interfaces file or restart networking services
#
# --help, -h:
# show help
#
# --bridge, -b
# configure interfaces as bridges. Assumes bridge-utils is already installed
#
# --interfaces-file, -f
# file to modify. defaults to /etc/network/interfaces
#
# --ip, -i
# list of static IPs to use per interface. can be used multiple times. format is: iface:ip:netmask:gateway. When combined with --bridge, use the bridge inteface names, they map like: eth0 -> br0. i.e.: eth0,10.0.0.1,255.0.0.0,10.10.0.2 becomes br0,10.0.0.1,255.0.0.0,10.10.0.2
#
# --restart-network, -r
# restart network interfaces after changing /etc/network/interfaces. mutually exclusive with --debug and/or --dry-run
#
# --usage, -U, -?:
# show usage
#
# --verbose, -V:
# display extra messages
#
# == Bugs
# * no validation of IPs if you mismatch IPv6 and IPv4 addresses. Use --dry-run until you're sure
#
# == Author
# Luis Mondesi <lemsx1@gmail.com>
#
# == License
# GPLv3
# 2010-04-28 13:42 EDT
#
# 1. open /etc/network/interfaces
# 2. setup ip via dhcp or static
# 3. optinally restart networking
#
# all this is done quietly unless --verbose
require 'getoptlong'
require 'rdoc/usage'
# helpers
class IfaceFileError < StandardError
end
def is_valid_ip?(ip)
return true if ip =~ /^\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}$/ or ip =~ /^[:[:xdigit:]]+$/
false
end
def is_valid_nm?(ip)
return true if ip =~ /^255\.(?:255|0)\.(?:255|0)\.(?:255|0)/ or ip =~ /[[:xdigit:]]+$/
false
end
# end helpers
opts = GetoptLong.new(
[ '--bridge', '-b', GetoptLong::NO_ARGUMENT ],
[ '--debug', '-D', GetoptLong::NO_ARGUMENT ],
[ '--help', '-h', GetoptLong::NO_ARGUMENT ],
[ '--interfaces', '-f', GetoptLong::REQUIRED_ARGUMENT ],
[ '--ip', '-i', GetoptLong::REQUIRED_ARGUMENT ],
[ '--usage', '-U', '-?', GetoptLong::NO_ARGUMENT ],
[ '--dry-run', '-n', GetoptLong::NO_ARGUMENT ],
[ '--restart-network', '-r', GetoptLong::NO_ARGUMENT ],
[ '--verbose', '-V', GetoptLong::NO_ARGUMENT ]
)
iface_file = "/etc/network/interfaces"
bridge=false
static=false
ip = Hash.new(&(p=lambda{|h,k| h[k] = Hash.new(&p)}))
debugging = false
dryrun = false
restartnet = false
verbose = false
opts.each do |opt, arg|
case opt
when '--help'
RDoc::usage
when '--usage'
RDoc::usage
when '--bridge'
bridge=true
when '--interfaces'
iface_file=arg.to_s.chomp
when '--ip'
static=true
_iface, _ip, _nm, _gw = arg.split(/,/)
# any field can be empty except the iface name itself
# we support IPv6 addresses too
RDoc::usage if not _iface or _iface =~ /^\s*$/
ip[_iface][:ip] = _ip if is_valid_ip? _ip
ip[_iface][:nm] = _nm if is_valid_nm? _nm
ip[_iface][:gw] = _gw if is_valid_ip? _gw
when '--debug'
dryrun=true
debugging=true
when '--dry-run'
dryrun=true
restartnet = false
when '--restart-network'
restartnet = true
when '--verbose'
verbose = true
end
end
if (Process.euid != 0)
puts "You must run this as root"
exit 1
end
begin
if dryrun
fd = STDOUT
else
fd = open(iface_file,"w+")
end
iflist = `lshw | grep 'logical name'|sed 's/.*: //'`
raise IfaceFileError, "No interfaces found" if iflist.size < 1
# std debian messages
fd.puts "# See interfaces(5) for information"
# loopback
fd.puts "auto lo"
fd.puts "iface lo inet loopback
"
if bridge
test ?x,"/usr/sbin/brctl" or raise "Command brctl not found"
# configure each interface as a bridge with dhcp
iflist.each do |net|
net.chomp!
next if not net =~ /^eth/ or net =~ /^wlan/
fd.puts "auto #{net}"
fd.puts "iface #{net} inet manual
"
ifnum = net.gsub(/[^[:digit:]]+/,"")
_net = "br#{ifnum}"
fd.puts "auto #{_net}"
if static
if ip[_net][:ip] =~ /^[:[:xdigit:]]+$/
fd.puts "iface #{_net} inet6 static"
else
fd.puts "iface #{_net} inet static"
end
fd.puts "\taddress #{ip[_net][:ip]}" if is_valid_ip? ip[_net][:ip]
fd.puts "\tnetmask #{ip[_net][:nm]}" if is_valid_nm? ip[_net][:nm]
fd.puts "\tgateway #{ip[_net][:gw]}" if is_valid_ip? ip[_net][:gw]
else
fd.puts "iface #{_net} inet dhcp"
end
fd.puts "\tbridge_ports #{net}"
fd.puts "\tbridge_stp on"
fd.puts "\tbridge_fd 0"
fd.puts "\tbridge_maxwait 0"
end
else
iflist.each do |net|
net.chomp!
next if not net =~ /^eth/
fd.puts "auto #{net}"
fd.puts "iface #{net} inet dhcp
"
end
end
if restartnet
unless debugging or dryrun
puts "Restarting networking" if verbose
`stop network-manager`
`start network-manager`
else
puts "Not restarting network due to --debug or --dry-run"
end
end
fd.close
rescue Errno::EACCES, IfaceFileError, RuntimeError => e
STDERR.puts e.message
exit 1
end
Tweets by @13m5
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