# # Shorewall-perl 4.1 -- /usr/share/shorewall-perl/Shorewall/IPAddrs.pm # # This program is under GPL [http://www.gnu.org/licenses/old-licenses/gpl-2.0.txt] # # (c) 2007 - Tom Eastep (teastep@shorewall.net) # # Complete documentation is available at http://shorewall.net # # This program is free software; you can redistribute it and/or modify # it under the terms of Version 2 of the GNU General Public License # as published by the Free Software Foundation. # # This program is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU General Public License for more details. # # You should have received a copy of the GNU General Public License # along with this program; if not, write to the Free Software # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. # # This module provides interfaces for dealing with IPv4 addresses, protocol names, and # port names. It also exports functions for validating protocol- and port- (service) # related constructs. # package Shorewall::IPAddrs; require Exporter; use Shorewall::Config qw( :DEFAULT split_list require_capability in_hex8); use strict; our @ISA = qw(Exporter); our @EXPORT = qw( ALLIPv4 TCP UDP ICMP SCTP validate_address validate_net decompose_net validate_host validate_range ip_range_explicit expand_port_range allipv4 rfc1918_neworks resolve_proto proto_name validate_port validate_portpair validate_port_list validate_icmp ); our @EXPORT_OK = qw( ); our $VERSION = 4.1.5; # # Some IPv4 useful stuff # our @allipv4 = ( '0.0.0.0/0' ); use constant { ALLIPv4 => '0.0.0.0/0' , ICMP => 1, TCP => 6, UDP => 17 , SCTP => 132 }; our @rfc1918_networks = ( "10.0.0.0/8", "172.16.0.0/12", "192.168.0.0/16" ); sub vlsm_to_mask( $ ) { my $vlsm = $_[0]; in_hex8 ( ( 0xFFFFFFFF << ( 32 - $vlsm ) ) && 0xFFFFFFFF ); } sub valid_address( $ ) { my $address = $_[0]; my @address = split /\./, $address; return 0 unless @address == 4; for my $a ( @address ) { return 0 unless $a =~ /^\d+$/ && $a < 256; } 1; } sub validate_address( $$ ) { my ( $addr, $allow_name ) = @_; my @addrs = ( $addr ); unless ( valid_address $addr ) { fatal_error "Invalid IP Address ($addr)" unless $allow_name; fatal_error "Unknown Host ($addr)" unless (@addrs = gethostbyname $addr); if ( defined wantarray ) { shift @addrs for (1..4); for ( @addrs ) { my (@a) = unpack('C4',$_); $_ = join('.', @a ); } } } defined wantarray ? wantarray ? @addrs : $addrs[0] : undef; } sub decodeaddr( $ ) { my $address = $_[0]; my @address = split /\./, $address; my $result = shift @address; for my $a ( @address ) { $result = ( $result << 8 ) | $a; } $result; } sub encodeaddr( $ ) { my $addr = $_[0]; my $result = $addr & 0xff; for my $i ( 1..3 ) { my $a = ($addr = $addr >> 8) & 0xff; $result = "$a.$result"; } $result; } sub validate_net( $$ ) { my ($net, $vlsm, $rest) = split( '/', $_[0], 3 ); my $allow_name = $_[1]; fatal_error "Missing address" if $net eq ''; fatal_error "An ipset name ($net) is not allowed in this context" if substr( $net, 0, 1 ) eq '+'; if ( defined $vlsm ) { fatal_error "Invalid VLSM ($vlsm)" unless $vlsm =~ /^\d+$/ && $vlsm <= 32; fatal_error "Invalid Network address ($_[0])" if defined $rest; fatal_error "Invalid IP address ($net)" unless valid_address $net; } else { fatal_error "Invalid Network address ($_[0])" if $_[0] =~ '/' || ! defined $net; validate_address $net, $_[1]; $vlsm = 32; } if ( defined wantarray ) { fatal_error "Internal Error in validate_net()" if $allow_name; if ( wantarray ) { ( decodeaddr( $net ) , $vlsm ); } else { "$net/$vlsm"; } } } sub validate_range( $$ ) { my ( $low, $high ) = @_; validate_address $low, 0; validate_address $high, 0; my $first = decodeaddr $low; my $last = decodeaddr $high; fatal_error "Invalid IP Range ($low-$high)" unless $first <= $last; } sub ip_range_explicit( $ ) { my $range = $_[0]; my @result; my ( $low, $high ) = split /-/, $range; validate_address $low, 0; push @result, $low; if ( defined $high ) { validate_address $high, 0; my $first = decodeaddr $low; my $last = decodeaddr $high; my $diff = $last - $first; fatal_error "Invalid IP Range ($range)" unless $diff >= 0 && $diff <= 256; while ( ++$first <= $last ) { push @result, encodeaddr( $first ); } } @result; } sub decompose_net( $ ) { my $net = $_[0]; return ( qw/0x00000000 0x00000000/ ) if $net eq '-'; ( $net, my $vlsm ) = validate_net( $net , 0 ); ( in_hex8( $net ) , vlsm_to_mask( $vlsm ) ); } sub validate_host( $$ ) { my ( $host, $allow_name ) = $_[0]; if ( $host =~ /^(\d+\.\d+\.\d+\.\d+)-(\d+\.\d+\.\d+\.\d+)$/ ) { validate_range $1, $2; } else { validate_net( $host, $allow_name ); } } sub allipv4() { @allipv4; } sub rfc1918_networks() { @rfc1918_networks } # # Protocol/port validation # our %nametoproto = ( all => 0, ALL => 0, icmp => 1, ICMP => 1, tcp => 6, TCP => 6, udp => 17, UDP => 17 ); our @prototoname = ( 'all', 'icmp', '', '', '', '', 'tcp', '', '', '', '', '', '', '', '', '', '', 'udp' ); # # Returns the protocol number if the passed argument is a valid protocol number or name. Returns undef otherwise # sub resolve_proto( $ ) { my $proto = $_[0]; my $number; $proto =~ /^(\d+)$/ ? $proto <= 65535 ? $proto : undef : defined( $number = $nametoproto{$proto} ) ? $number : scalar getprotobyname $proto; } sub proto_name( $ ) { my $proto = $_[0]; $proto =~ /^(\d+)$/ ? $prototoname[ $proto ] || scalar getprotobynumber $proto : $proto } sub validate_port( $$ ) { my ($proto, $port) = @_; my $value; if ( $port =~ /^(\d+)$/ ) { return $port if $port <= 65535; } else { $proto = getprotobyname $proto if $proto =~ /^(\d+)$/; $value = getservbyname( $port, $proto ); } fatal_error "Invalid/Unknown $proto port/service ($port)" unless defined $value; $value; } sub validate_portpair( $$ ) { my ($proto, $portpair) = @_; fatal_error "Invalid port range ($portpair)" if $portpair =~ tr/:/:/ > 1; $portpair = "0$portpair" if substr( $portpair, 0, 1 ) eq ':'; $portpair = "${portpair}65535" if substr( $portpair, -1, 1 ) eq ':'; my @ports = split /:/, $portpair, 2; $_ = validate_port( $proto, $_) for ( @ports ); if ( @ports == 2 ) { fatal_error "Invalid port range ($portpair)" unless $ports[0] < $ports[1]; } join ':', @ports; } sub validate_port_list( $$ ) { my $result = ''; my ( $proto, $list ) = @_; my @list = split_list( $list, 'port' ); if ( @list > 1 && $list =~ /:/ ) { require_capability( 'XMULTIPORT' , 'Port ranges in a port list', '' ); } $proto = proto_name $proto; for ( @list ) { my $value = validate_portpair( $proto , $_ ); $result = $result ? join ',', $result, $value : $value; } $result; } my %icmp_types = ( any => 'any', 'echo-reply' => 0, 'destination-unreachable' => 3, 'network-unreachable' => '3/0', 'host-unreachable' => '3/1', 'protocol-unreachable' => '3/2', 'port-unreachable' => '3/3', 'fragmentation-needed' => '3/4', 'source-route-failed' => '3/5', 'network-unknown' => '3/6', 'host-unknown' => '3/7', 'network-prohibited' => '3/9', 'host-prohibited' => '3/10', 'TOS-network-unreachable' => '3/11', 'TOS-host-unreachable' => '3/12', 'communication-prohibited' => '3/13', 'host-precedence-violation' => '3/14', 'precedence-cutoff' => '3/15', 'source-quench' => 4, 'redirect' => 5, 'network-redirect' => '5/0', 'host-redirect' => '5/1', 'TOS-network-redirect' => '5/2', 'TOS-host-redirect' => '5/3', 'echo-request' => '8', 'router-advertisement' => 9, 'router-solicitation' => 10, 'time-exceeded' => 11, 'ttl-zero-during-transit' => '11/0', 'ttl-zero-during-reassembly' => '11/1', 'parameter-problem' => 12, 'ip-header-bad' => '12/0', 'required-option-missing' => '12/1', 'timestamp-request' => 13, 'timestamp-reply' => 14, 'address-mask-request' => 17, 'address-mask-reply' => 18 ); sub validate_icmp( $ ) { my $type = $_[0]; my $value = $icmp_types{$type}; return $value if defined $value; if ( $type =~ /^(\d+)(\/(\d+))?$/ ) { return $type if $1 < 256 && ( ! $2 || $3 < 256 ); } fatal_error "Invalid ICMP Type ($type)" } sub expand_port_range( $$ ) { my ( $proto, $range ) = @_; my ( $first, $last ) = split /:/, $range, 2; if ( defined $last ) { my @result; ( $first , $last ) = ( validate_port( $proto, $first ) , validate_port( $proto, $last ) ); while ( $first <= $last ) { my $mask = 0xffff; my $y = 2; my $z = 1; while ( ( $first % $y ) == 0 && ( $first + $y ) < $last ) { $mask <<= 1; $z = $y; $y <<= 1; } push @result, sprintf( '%04x', $first ) , sprintf( '%04x' , $mask & 0xffff ); $first += $z; } fatal_error "Invalid port range ($range)" unless @result; @result; } else { ( sprintf( '%04x' , validate_port( $proto, $first ) ) , 'ffff' ); } } 1;