iftools/SRC/ifup

#!/usr/bin/perl

use strict;
use warnings;

use IPC::Open3;
use IO::Select;
use Fcntl qw( LOCK_EX LOCK_NB );
use Data::Dumper;

open( SELF, "<$0" ) || error( int( $! ), "open(): $0: $!" );
flock( SELF, LOCK_EX|LOCK_NB ) || error( -1, "Another instance is running" );

use constant CONFDIR => '/etc';
use constant CONFIGFILE => CONFDIR . '/network.conf';
use constant NOACT => eval {
	for ( my $i = 0; $i <= $#ARGV; $i++ ) {
		if ( $ARGV[$i] eq '-n' || $ARGV[$i] eq '--no-act' ) {
			splice( @ARGV, $i, 1 );

			return( 1 );
			}
		}

	return( 0 );
	};
use constant VERBOSE => eval {
	for ( my $i = 0; $i <= $#ARGV; $i++ ) {
		if ( $ARGV[$i] eq '-v' || $ARGV[$i] eq '--verbose' ) {
			splice( @ARGV, $i, 1 );

			return( 1 );
			}
		}

	return( 0 );
	};
use constant VERSION => '0.1';

sub aliasdown {
	my $alias = shift;
	my $runningconf = shift;
	my $aliases = $runningconf->{$alias->{'dev'}}{'aliases'};
	my $result;

	if ( my $running = $aliases->{$alias->{'name'}} ) {
		if ( VERBOSE ) {
			print "Deleting $running->{'address'}"
				. " from $alias->{'dev'}"
				. " (label $alias->{'dev'}:"
				. "$alias->{'name'})\n";
			}

		$result = runcmd( "ip address delete"
			. " $running->{'address'}"
			. " dev $running->{'dev'} label"
			. " $running->{'dev'}:$alias->{'name'}" );

		if ( VERBOSE ) {
			if ( $result->{'stdout'} ) {
				print $result->{'stdout'};
				}
			if ( $result->{'stderr'} ) {
				print STDERR $result->{'stderr'};
				}
			}

		return( $result->{'stat'} );
		}
	}

sub aliasup {
	my $alias = shift;
	my $runningconf = shift;
	my $dev = $alias->{'dev'};
	my $name = $alias->{'name'};
	my $result;

	if ( my $old = $runningconf->{$dev}{'aliases'}{$name} ) {
		if ( $old->{'address'} eq $alias->{'address'} &&
		$old->{'dev'} eq $alias->{'dev'} &&
		$old->{'name'} eq $alias->{'name'} ) {
			if ( VERBOSE ) {
				print STDERR "Interface $dev:$name"
					. " is already up\n";
				}

			return( 1 );
			}

		if ( my $retval = aliasdown( $old, $runningconf ) ) {
			return( $retval );
			}
		}

	if ( VERBOSE ) {
		print "Adding $alias->{'address'} to $alias->{'dev'}"
			. " (label $alias->{'dev'}"
			. ":$alias->{'name'})\n";
		}

	$result = runcmd( "ip address add $alias->{'address'}"
		. " dev $alias->{'dev'}"
		. " label $alias->{'dev'}:$alias->{'name'}" );

	if ( VERBOSE ) {
		if ( $result->{'stdout'} ) {
			print $result->{'stdout'};
			}
		if ( $result->{'stderr'} ) {
			print STDERR $result->{'stderr'};
			}
		}

	return( $result->{'stat'} );
	}

sub cidr2netmask {
	my $cidr = shift;
	my $bit = ( 2 ** ( 32 - $cidr ) ) - 1;
	my $full_mask = unpack( 'N', pack( 'C4', 255,255,255,255 ) );
	my $netmask = join( '.', unpack( 'C4', pack( 'N',
		( $full_mask ^ $bit ) ) ) );

	return( $netmask );
	}

sub error {
	my $status = shift;
	my $errstr = shift;
	my $level = 1;
	my @stack = ();

	chomp( $errstr );

	print "\n";

	print STDERR ( caller() )[1] .":\n  $errstr at line "
		. ( caller() )[2] . "\n";

	if ( VERBOSE ) {
		if ( caller( $level ) ) {
			print "\n=== Stack Trace ===\n";
			}

		while ( my @trace = caller( $level++ ) ) {
			print STDERR "  $trace[1]:\n"
                                . "    $trace[3]() called at line $trace[2]\n";
                        }
                }

        print "\n";

        if ( $status ) {
                exit( $status );
                }
        }

sub getroutes {
	my $routes = {};
	my $result = runcmd( 'ip route show' );

	if ( $result->{'stat'} || ! $result->{'stdout'} ) {
		return;
		}

	open( my $fh, '<', \$result->{'stdout'} );

	while ( <$fh> ) {
		if ( $_ =~ /^(\S+)\s+via\s+(\S+)\s+dev\s+(\S+)/ ) {
			$routes->{$1}{'via'} = $2;
			$routes->{$1}{'dev'} = $3;
			}
		}

	close( $fh );

	return( $routes );
	}

sub ifdown {
	my $iface = shift;
	my $result = {};
	my $stat = 0;

	if ( VERBOSE ) {
		print "Flushing interface $iface->{'name'}\n";
		}

	$result = runcmd( "ip addr flush dev $iface->{'name'}" );

	if ( $result->{'stat'} ) {
		$stat = $result->{'stat'};
		}

	if ( VERBOSE ) {
		if ( $result->{'stdout'} ) {
			print $result->{'stdout'};
			}
		if ( $result->{'stderr'} ) {
			print STDERR $result->{'stderr'};
			}

		print "Bringing down interface $iface->{'name'}\n";
		}

	$result = runcmd( "ip link set $iface->{'name'} down" );

	if ( $result->{'stat'} ) {
		$stat = $result->{'stat'};
		}

	if ( VERBOSE ) {
		if ( $result->{'stdout'} ) {
			print $result->{'stdout'};
			}
		if ( $result->{'stderr'} ) {
			print STDERR $result->{'stderr'};
			}
		}

	return( $stat );
	}

sub ifup {
	my $iface = shift;
	my $runningconf = shift;
	my $routes = getroutes();
	my $result;
	my $stat = 0;

	if ( my $old = $runningconf->{$iface->{'name'}} ) {
		if ( ( $old->{'address'} && $iface->{'address'} &&
		$old->{'address'} eq $iface->{'address'} ) ||
		( $old->{'state'} eq 'UP' && $iface->{'inet'} eq 'dhcp' ) ) {
			if ( VERBOSE ) {
				print STDERR "Interface $iface->{'name'}"
					. " is already up\n";
				}

			return;
			}

		if ( VERBOSE ) {
			print "Flushing interface $iface->{'name'}\n";
			}

		$result = runcmd( "ip addr flush dev $iface->{'name'}" );

		if ( VERBOSE ) {
			if ( $result->{'stdout'} ) {
				print $result->{'stdout'};
				}
			if ( $result->{'stderr'} ) {
				print STDERR $result->{'stderr'};
				}
			}

		if ( $result->{'stat'} ) {
			return( $result->{'stat'} );
			}
		}

	if ( $iface->{'macaddr'} ) {
		if ( VERBOSE ) {	
			print "Setting MAC address on interface"
				. " $iface->{'name'} to $iface->{'macaddr'}\n";
			}

		$result = runcmd( "ip link set dev $iface->{'name'}"
			. " address $iface->{'macaddr'}" );

		if ( VERBOSE ) {
			if ( $result->{'stdout'} ) {
				print $result->{'stdout'};
				}
			if ( $result->{'stderr'} ) {
				print STDERR $result->{'stderr'};
				}
			}

		if ( $result->{'stat'} ) {
			return( $result->{'stat'} );
			}
		}

	if ( VERBOSE ) {	
		print "Bringing up interface $iface->{'name'}\n";
		}

	if ( $iface->{'inet'} && $iface->{'inet'} eq 'static' ) {
		if ( VERBOSE ) {
			print "Setting address to $iface->{'address'}"
				. " on interface $iface->{'name'}\n";
			}

		$result = runcmd( "ip address add $iface->{'address'}"
			. " dev $iface->{'name'}" );

		if ( VERBOSE ) {
			if ( $result->{'stdout'} ) {
				print $result->{'stdout'};
				}
			if ( $result->{'stderr'} ) {
				print STDERR $result->{'stderr'};
				}
			}

		if ( $result->{'stat'} ) {
			return( $result->{'stat'} );
			}
		}
	elsif ( $iface->{'inet'} && $iface->{'inet'} eq 'loopback' &&
	! $runningconf->{$iface->{'name'}}{'name'} ) {
		if ( VERBOSE ) {
			print "Setting address to $iface->{'address'}"
				. " on interface $iface->{'name'}\n";
			}

		$result = runcmd( "ip -d address add $iface->{'address'}"
			. " dev $iface->{'name'}" );

		if ( VERBOSE ) {
			if ( $result->{'stdout'} ) {
				print $result->{'stdout'};
				}
			if ( $result->{'stderr'} ) {
				print STDERR $result->{'stderr'};
				}
			}

		if ( $result->{'stat'} ) {
			return( $result->{'stat'} );
			}
		}
	elsif ( $iface->{'inet'} && $iface->{'inet'} eq 'dhcp' ) {
		if ( -f '/var/run/dhclient.pid' ) {
			system( "dhclient -r $iface->{'name'}" );
			}

		if ( VERBOSE ) {
			print "Starting dhclient for $iface->{'name'}\n";
			}

		$result = runcmd( "dhclient $iface->{'name'}" );

		if ( VERBOSE ) {
			if ( $result->{'stdout'} ) {
				print $result->{'stdout'};
				}
			if ( $result->{'stderr'} ) {
				print STDERR $result->{'stderr'};
				}
			}

		if ( $result->{'stat'} ) {
			return( $result->{'stat'} );
			}
		}

	$result = runcmd( "ip link set $iface->{'name'} up" );

	if ( VERBOSE ) {
		if ( $result->{'stdout'} ) {
			print $result->{'stdout'};
			}
		if ( $result->{'stderr'} ) {
			print STDERR $result->{'stderr'};
			}
		}

	if ( $result->{'stat'} ) {
		return( $result->{'stat'} );
		}

	if ( ! $routes->{'default'} && $iface->{'gateway'} ) {
		if ( VERBOSE ) {
			print "Adding default gateway $iface->{'gateway'}\n";
			}

		$result = runcmd( "ip route add default"
			. " via $iface->{'gateway'}" );

		if ( VERBOSE ) {
			if ( $result->{'stdout'} ) {
				print $result->{'stdout'};
				}
			if ( $result->{'stderr'} ) {
				print STDERR $result->{'stderr'};
				}
			}

		if ( $result->{'stat'} ) {
			return( $result->{'stat'} );
			}
		}
	elsif ( $routes->{'default'}{'via'} && $iface->{'gateway'} &&
	$routes->{'default'}{'via'} ne $iface->{'gateway'} &&
	$routes->{'default'}{'dev'} eq $iface->{'name'} ) {
		if ( VERBOSE ) {
			print "Changing default gateway to"
				. " $iface->{'gateway'}\n";
			}

		$result = runcmd( "ip route delete default via"
			. " $routes->{'default'}{'via'} dev $iface->{'name'}" );

		if ( VERBOSE ) {
			if ( $result->{'stdout'} ) {
				print $result->{'stdout'};
				}
			if ( $result->{'stderr'} ) {
				print STDERR $result->{'stderr'};
				}
			}

		if ( $result->{'stat'} ) {
			return( $result->{'stat'} );
			}

		$result = runcmd( "ip route add default"
			. " via $iface->{'gateway'}" );

		if ( VERBOSE ) {
			if ( $result->{'stdout'} ) {
				print $result->{'stdout'};
				}
			if ( $result->{'stderr'} ) {
				print STDERR $result->{'stderr'};
				}
			}

		if ( $result->{'stat'} ) {
			return( $result->{'stat'} );
			}
		}

	if ( $iface->{'routes'} ) {
		foreach my $target ( keys( %{$iface->{'routes'}} ) ) {
			if ( VERBOSE ) {
				print "Adding route $target via"
					. " $iface->{'routes'}{$target}"
					. " dev $iface->{'name'}\n";
				}

			system( "ip route add $target via"
				. " $iface->{'routes'}{$target}"
				. " dev $iface->{'name'}" );
			}
		}
	}

sub listfiles {
	my $dir = shift;
	my $files = [];
	my $sorted = [];

	if ( ! -d $dir ) {
		return;
		}

	opendir( DIR, $dir ) || error( int( $! ), "opendir(): $dir: $!" );

	while ( readdir( DIR ) ) {
		if ( ! -f "$dir/$_" || $_ =~ /^\./ ) {
			next;
			}

		push ( @$files, $_ );
		}

	@$sorted = sort( @$files );

	return( $sorted );
	}

sub netmask2cidr {
	my $netmask = shift;
	my $bits = { 
		0 => 0,
		128 => 1,
		192 => 2,
		224 => 3,
		240 => 4,
		248 => 5,
		252 => 6,
		254 => 7,
		255 => 8 
		};
	my $lastoct;
	my $cidr = 0;

	foreach ( split( /\./, $netmask ) ) {
		if ( ( $lastoct && $lastoct != 255 && $_ != 0 ) ||
		! defined( $bits->{$_} ) ) {
			error( int( $! ), "netmask2cidr(): $netmask:"
				. " Invalid netmask" );
			}

		$cidr += $bits->{$_};
		$lastoct = $_;
		}

	return( $cidr );
	}

sub readconf {
	my $file = shift;
	my $conf = shift || {};
	my $iface;

	open( my $config, "<$file" ) || error( int( $! ), "open(): $file: $!" );
	
	while ( <$config> ) {
		if ( $_ =~ /^\s*#/ ) {
			next;
			}

		if ( $_ =~ /source-directory\s+(\S+)/ ) {
			my $path = $1;
			my $files;

			if ( substr( $path, 0, 1 ) ne '/' ) {
				$path = CONFDIR . "/$path";
				}

			$files = listfiles( $path );

			foreach my $file ( @$files ) {
				readconf( "$path/$file", $conf );
				}
			}
		elsif ( $_ =~ /auto\s+(\S+)/ && $1 =~ /^(\S+):(\S+)$/ ) {
			$conf->{$1}{'aliases'}{$2}{'auto'} = 1;
			}
		elsif ( $_ =~ /auto\s+(\S+)/ ) {
			$conf->{$1}{'auto'} = 1;
			}
		elsif ( $_ =~ /iface\s+(\S+):(\S+)/ ) {
			$iface = "$1:$2";
			$conf->{$1}{'aliases'}{$2}{'dev'} = $1;
			$conf->{$1}{'aliases'}{$2}{'name'} = $2;
			$conf->{$1}{'aliases'}{$2}{'cnt'} =
				keys( %{$conf->{$1}{'aliases'}} );
			}
		elsif ( $_ =~ /iface\s+(\S+)\s+(\S+)\s+(\S+)/ ) {
			$iface = $1;

			if ( $conf->{$iface}{'inet'} ) {
				error( -1, "Multiple instances of $iface"
					. " in $file" );
				}

			$conf->{$iface}{$2} = $3;
			$conf->{$iface}{'name'} = $iface;

			if ( $3 eq 'loopback' ) {
				$conf->{$iface}{'address'} = '127.0.0.1/8';
				}

			$conf->{$iface}{'cnt'} = scalar( keys( %$conf ) );
			}
		elsif ( $_ =~ /route\s+(\S+)\s+via\s+(\S+)/ ) {
			$conf->{$iface}{'routes'}{$1} = $2;
			}
		elsif ( $iface && $_ =~ /^\s*(\S+)\s+(\S+)/ ) {
			my ( $attr, $value ) = ( $1, $2 );

			if ( $iface =~ /^(\S+):(\S+)/ ) {
				$conf->{$1}{'aliases'}{$2}{$attr} = $value;
				}
			else {
				$conf->{$iface}{$attr} = $value;
				}
			}
		elsif ( $iface && $_ =~ /^\s*(\S+)\s+(\S+)/ ) {
			$conf->{$iface}{$1} = $2;
			}
		}

	close( $config );

	foreach my $devname ( keys( %$conf ) ) {
		my $dev = $conf->{$devname};

		if ( $dev->{'address'} && $dev->{'netmask'} ) {
			$dev->{'address'} .= '/'
				. netmask2cidr( $dev->{'netmask'} );

			undef( $dev->{'netmask'} );
			}

		if ( ! keys( %{$dev->{'aliases'}} ) ) {
			next;
			}

		foreach my $aliasname ( keys( %{$dev->{'aliases'}} ) ) {
			my $alias = $dev->{'aliases'}{$aliasname};

			if ( $alias->{'address'} && $alias->{'netmask'} ) {
				$alias->{'address'} .= '/'
					. netmask2cidr( $alias->{'netmask'} );

				undef( $alias->{'netmask'} );
				}
			}
		}

	return( $conf );
	}

sub runcmd {
	if ( NOACT ) {
		return( { stat => 0 } );;
		}

	my $cmd = shift;
	my $result = {
		stdout => '',
		stderr => '',
		stat => ''
		};
	my $sel = IO::Select->new();
	my $pid = eval {
		return( open3( \*CHLDIN, \*CHLDOUT, \*CHLDERR, $cmd ) );
		} || error( int( $! ), "open3(): $cmd: $!" );

	close( CHLDIN );

	$sel->add( *CHLDOUT, *CHLDERR );

	while ( my @fhs = $sel->can_read ) {
		foreach my $fh ( @fhs ) {
			if ( eof( $fh ) ) {
				$sel->remove( $fh );

				next;
				}

			if ( fileno( $fh ) == fileno( *CHLDOUT ) ) {
				$result->{'stdout'} .= <$fh>;
				}
			elsif ( fileno( $fh ) == fileno( *CHLDERR ) ) {
				$result->{'stderr'} .= <$fh>;
				}
			}
		}

	close( CHLDOUT );
	close( CHLDERR );

	waitpid( $pid, 0 );
	$result->{'stat'} = $? >> 8;

	return( $result );
	}

sub runningconf {
	my $cmd = 'ip -d address show';
	my $sel = IO::Select->new();
	my $pid = eval {
		return( open3( \*CHLDIN, \*CHLDOUT, \*CHLDERR, $cmd ) );
		} || error( int( $! ), "open3(): $cmd: $!" );
	my $stat;
	my $stdout = '';
	my $stderr = '';
	my $runningconf = {};
	my $macaddr;
	my $dev;

	close( CHLDIN );

	$sel->add( *CHLDOUT, *CHLDERR );

	while ( my @fhs = $sel->can_read ) {
		foreach my $fh ( @fhs ) {
			if ( eof( $fh ) ) {
				$sel->remove( $fh );

				next;
				}

			if ( fileno( $fh ) == fileno( *CHLDOUT ) ) {
				$stdout .= <$fh>;
				}
			elsif ( fileno( $fh ) == fileno( *CHLDERR ) ) {
				$stderr .= <$fh>;
				}
			}
		}

	close( CHLDOUT );
	close( CHLDERR );

	waitpid( $pid, 0 );
	$stat = $? >> 8;

	if ( $stat ) {
		error( int( $! ), "open3: $cmd: $stderr" );
		}

	open( my $fh, '<', \$stdout ) || error( int( $! ), "open(): $!" );

	while ( <$fh> ) {
		if ( $_ =~ /^\d+:\s*(\S+):/ ) {
			$dev = $1;
			}

		if ( $_ =~ /\s+mtu\s+(\d+)/ ) {
			$runningconf->{$dev}{'mtu'} = $1;
			}
		if ( $_ =~ /\s+qdisc\s+(\S+)/ ) {
			$runningconf->{$dev}{'qdisc'} = $1;
			}
		if ( $_ =~ /\s+state\s+(\S+)/ ) {
			$runningconf->{$dev}{'state'} = $1;
			}
		if ( $_ =~ /\s+group\s+(\S+)/ ) {
			$runningconf->{$dev}{'group'} = $1;
			}
		if ( $_ =~ /\s+qlen\s+(\S+)/ ) {
			$runningconf->{$dev}{'qlen'} = $1;
			}
		if ( $_ =~ /^\s+link\/(\S+)\s+(\S+)/ ) {
			$runningconf->{$dev}{'link'} = $1;
			$runningconf->{$dev}{'macaddr'} = $2;
			}
		if ( $_ =~ /\s+promiscuity\s+(\S+)/ ) {
			$runningconf->{$dev}{'promiscuity'} = $1;
			}

		if ( $_ =~ /^\s+inet\s+(\S+).*\s+(\S+):(\S+)/ ) {
			$runningconf->{$2}{'aliases'}{$3}{'address'} = $1;
			$runningconf->{$2}{'aliases'}{$3}{'dev'} = $dev;
			$runningconf->{$2}{'aliases'}{$3}{'name'} = $3;
			}
		elsif ( $_ =~ /^\s+inet\s+(\S+).*(\S+)$/ ) {
			if ( $runningconf->{$dev}{'address'} ) {
				next;
				}

			$runningconf->{$dev}{'address'} = $1;
			}
		}

	close( $fh );

	return( $runningconf );
	}

my $conf = readconf( CONFIGFILE );
my $runningconf = runningconf();
my $self = ( split( '/', $0 ) )[-1];
my $ifaces = [];
my $all = eval {
	for ( my $i = 0; $i <= $#ARGV; $i++ ) {
		if ( $ARGV[$i] eq '-a' || $ARGV[$i] eq '--all' ) {
			splice( @ARGV, $i, 1 );

			return( 1 );
			}
		}
	};
my $stat = 0;
#print Dumper( $conf ); exit;

if ( grep( $_ eq '-h' || $_ eq '--help', @ARGV ) ) {
	print "Usage: $self [OPTIONS] [INTERFACES]\n";

	if ( $self eq 'ifup' ) {
		print "Bring a network interface up\n\n";
		}
	elsif ( $self eq 'ifdown' ) {
		print "Bring a network interface down\n\n";
		}
	elsif ( $self eq 'ifreload' ) {
		print "Reload interface configuration\n\n";
		}
	elsif ( $self eq 'ifquery' ) {
		print "View current status of interfaces\n\n";
		}

	print "Options:\n"
		. "\t-a, --all\t\tperform actions on all 'auto' interfaces\n"
		. "\t-h, --help\t\tprint usage information\n";

	if ( $self ne 'ifquery' ) {
		print "\t-n, --no-act\t\tdisplay actions without taking them\n"
			. "\t-v, --verbose\t\tdisplay actions as they occur\n";
		}

	print "\t-V, --version\t\tdisplay version information\n"; 

	exit( 0 );
	}
elsif ( grep( $_ eq '-V' || $_ eq '--version', @ARGV ) ) {
	print "iftools version " . VERSION . "\n";

	exit( 0 );
	}

if ( ! $all ) {
	foreach ( @ARGV ) {
		( my $dev = $_ ) =~ s/:.*//;

		if ( $runningconf->{$dev} ) {
			push( @$ifaces, $_ );
			}
		elsif ( VERBOSE ) {
			print STDERR "$_: No such device\n";
			}
		}
	}
else {
	foreach ( sort { $conf->{$a}{'cnt'} <=> $conf->{$b}{'cnt'} }
	( keys( %$conf ) ) ) {
		( my $dev = $_ ) =~ s/:.*//;

		if ( $self eq 'ifup' && ! $conf->{$_}{'auto'} ) {
			next;
			}

		if ( $runningconf->{$dev} ) {
			push( @$ifaces, $_ );
			}
		elsif ( VERBOSE ) {
			print STDERR "$_: No such device\n";

			next;
			}

		foreach my $alias ( sort {
		$conf->{$dev}{'aliases'}{$a}{'cnt'} <=>
		$conf->{$dev}{'aliases'}{$b}{'cnt'} }
		keys( %{$conf->{$dev}{'aliases'}} ) ) {
			push( @$ifaces, "$dev:$alias" );
			}
		}
	}

foreach my $iface ( @$ifaces ) {
	if ( $self eq 'ifup' ) {
		if ( $iface =~ /^(\S+):(\S+)/ ) {
			$stat = aliasup( $conf->{$1}{'aliases'}{$2},
				$runningconf ) || $stat;
			}
		else {
			$stat = ifup( $conf->{$iface}, $runningconf ) || $stat;
			}
		}
	elsif ( $self eq 'ifdown' ) {
		if ( $iface =~ /^(\S+):(\S+)/ ) {
			$stat = aliasdown( $conf->{$1}{'aliases'}{$2},
				$runningconf ) || $stat;
			}
		else {
			$stat = ifdown( $conf->{$iface}, $runningconf ) ||
				$stat;
			}
		}
	elsif ( $self eq 'ifreload' ) {
		if ( $iface =~ /^(\S+):(\S+)/ ) {
			$stat = aliasdown( $conf->{$1}{'aliases'}{$2},
				$runningconf ) || $stat;
			$runningconf = runningconf();
			$stat = aliasup( $conf->{$1}{'aliases'}{$2},
				$runningconf ) || $stat;
			}
		else {
			$stat = ifdown( $conf->{$iface}, $runningconf ) ||
				$stat;
			$runningconf = runningconf();
			$stat = ifup( $conf->{$iface}, $runningconf ) ||
				$stat;
			}
		}
	elsif ( $self eq 'ifquery' ) {
		if ( $iface =~ /^\S+:\S+/ ) {
			next;
			}
		elsif ( ! $runningconf->{$iface} ) {
			$runningconf->{$iface} = {
				state => 'No such device',
				address => '',
				macaddr => ''
				};
			}

		print "[$iface]\n"
			. "  State: $runningconf->{$iface}{'state'}\n";

		if ( $runningconf->{$iface}{'address'} ) {
			print "  Address: $runningconf->{$iface}{'address'}\n";
			}
		if ( $runningconf->{$iface}{'macaddr'} ) {
			print "  MAC: $runningconf->{$iface}{'macaddr'}\n";
			}

		foreach my $name ( sort( keys(
		%{$runningconf->{$iface}{'aliases'}} ) ) ) {
			my $alias = $runningconf->{$iface}{'aliases'}{$name};
			print "[$iface:$name]\n"
				. "  Address: $alias->{'address'}\n";
			}
		}

	$runningconf = runningconf();
	}

close( SELF );
exit( $stat );