# # Shorewall 4.4 -- /usr/share/shorewall/Shorewall/Misc.pm # # This program is under GPL [http://www.gnu.org/licenses/old-licenses/gpl-2.0.txt] # # (c) 2007,2008,2009,2010,2011 - 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 ofs # 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 contains those routines that don't seem to fit well elsewhere. It # was carved from the Rules module in 4.4.16. # package Shorewall::Misc; require Exporter; use Shorewall::Config qw(:DEFAULT :internal); use Shorewall::IPAddrs; use Shorewall::Zones; use Shorewall::Chains qw(:DEFAULT :internal); use Shorewall::Rules; use Shorewall::Proc; use strict; our @ISA = qw(Exporter); our @EXPORT = qw( process_tos setup_ecn add_common_rules setup_mac_lists process_routestopped compile_stop_firewall generate_matrix ); our @EXPORT_OK = qw( initialize ); our $VERSION = 'MODULEVERSION'; my $family; # # Rather than initializing globals in an INIT block or during declaration, # we initialize them in a function. This is done for two reasons: # # 1. Proper initialization depends on the address family which isn't # known until the compiler has started. # # 2. The compiler can run multiple times in the same process so it has to be # able to re-initialize its dependent modules' state. # sub initialize( $ ) { $family = shift; } sub process_tos() { my $chain = have_capability( 'MANGLE_FORWARD' ) ? 'fortos' : 'pretos'; my $stdchain = have_capability( 'MANGLE_FORWARD' ) ? 'FORWARD' : 'PREROUTING'; my %tosoptions = ( 'minimize-delay' => 0x10 , 'maximize-throughput' => 0x08 , 'maximize-reliability' => 0x04 , 'minimize-cost' => 0x02 , 'normal-service' => 0x00 ); if ( my $fn = open_file 'tos' ) { my $first_entry = 1; my ( $pretosref, $outtosref ); first_entry( sub { progress_message2 "$doing $fn..."; $pretosref = ensure_chain 'mangle' , $chain; $outtosref = ensure_chain 'mangle' , 'outtos'; } ); while ( read_a_line ) { my ($src, $dst, $proto, $ports, $sports , $tos, $mark ) = split_line 7, 'tos file entry', { source => 0, dest => 1, proto => 2, dport => 3, sport => 4, tos => 5, mark => 6 } ; $first_entry = 0; fatal_error 'A value must be supplied in the TOS column' if $tos eq '-'; if ( defined ( my $tosval = $tosoptions{"\L$tos"} ) ) { $tos = $tosval; } else { my $val = numeric_value( $tos ); fatal_error "Invalid TOS value ($tos)" unless defined( $val ) && $val < 0x1f; } my $chainref; my $restriction = NO_RESTRICT; my ( $srczone , $source , $remainder ); if ( $family == F_IPV4 ) { ( $srczone , $source , $remainder ) = split( /:/, $src, 3 ); fatal_error 'Invalid SOURCE' if defined $remainder; } elsif ( $src =~ /^(.+?):<(.*)>\s*$/ || $src =~ /^(.+?):\[(.*)\]\s*$/ ) { $srczone = $1; $source = $2; } else { $srczone = $src; } if ( $srczone eq firewall_zone ) { $chainref = $outtosref; $src = $source || '-'; $restriction = OUTPUT_RESTRICT; } else { $chainref = $pretosref; $src =~ s/^all:?//; } $dst =~ s/^all:?//; expand_rule $chainref , $restriction , do_proto( $proto, $ports, $sports ) . do_test( $mark , $globals{TC_MASK} ) , $src , $dst , '' , "TOS --set-tos $tos" , '' , 'TOS' , ''; } unless ( $first_entry ) { add_ijump( $mangle_table->{$stdchain}, j => $chain ) if $pretosref->{referenced}; add_ijump( $mangle_table->{OUTPUT}, j => 'outtos' ) if $outtosref->{referenced}; } } } # # Setup ECN disabling rules # sub setup_ecn() { my %interfaces; my @hosts; if ( my $fn = open_file 'ecn' ) { first_entry( sub { progress_message2 "$doing $fn..."; require_capability 'MANGLE_ENABLED', 'Entries in the ecn file', ''; warning_message 'ECN will not be applied to forwarded packets' unless have_capability 'MANGLE_FORWARD'; } ); while ( read_a_line ) { my ($interface, $hosts ) = split_line 2, 'ecn file entry', { interface => 0, hosts => 1 }; fatal_error 'INTERFACE must be specified' if $interface eq '-'; fatal_error "Unknown interface ($interface)" unless known_interface $interface; $interfaces{$interface} = 1; $hosts = ALLIP if $hosts eq '-'; for my $host( split_list $hosts, 'address' ) { validate_host( $host , 1 ); push @hosts, [ $interface, $host ]; } } if ( @hosts ) { my @interfaces = ( keys %interfaces ); progress_message "$doing ECN control on @interfaces..."; for my $interface ( @interfaces ) { my $chainref = ensure_chain 'mangle', ecn_chain( $interface ); add_ijump $mangle_table->{POSTROUTING} , j => $chainref, p => 'tcp', imatch_dest_dev( $interface ) if have_capability 'MANGLE_FORWARD'; add_ijump $mangle_table->{OUTPUT}, j => $chainref, p => 'tcp', imatch_dest_dev( $interface ); } for my $host ( @hosts ) { add_ijump( $mangle_table->{ecn_chain $host->[0]}, j => 'ECN', targetopts => '--ecn-tcp-remove', p => 'tcp', imatch_dest_net( $host->[1] ) ); } } } } sub add_rule_pair( $$$$ ) { my ($chainref , $predicate , $target , $level ) = @_; log_rule( $level, $chainref, "\U$target", $predicate ) if supplied $level; add_jump( $chainref , $target, 0, $predicate ); } sub setup_blacklist() { my $zones = find_zones_by_option 'blacklist', 'in'; my $zones1 = find_zones_by_option 'blacklist', 'out'; my $chainref; my $chainref1; my ( $level, $disposition ) = @config{'BLACKLIST_LOGLEVEL', 'BLACKLIST_DISPOSITION' }; my $audit = $disposition =~ /^A_/; my $target = $disposition eq 'REJECT' ? 'reject' : $disposition; my $orig_target = $target; # # We go ahead and generate the blacklist chains and jump to them, even if they turn out to be empty. That is necessary # for 'refresh' to work properly. # if ( @$zones || @$zones1 ) { $chainref = dont_delete new_standard_chain 'blacklst' if @$zones; $chainref1 = dont_delete new_standard_chain 'blackout' if @$zones1; if ( supplied $level ) { my $logchainref = new_standard_chain 'blacklog'; $target =~ s/A_//; $target = 'reject' if $target eq 'REJECT'; log_rule_limit( $level , $logchainref , 'blacklst' , $disposition , "$globals{LOGLIMIT}" , '', 'add', '' ); add_ijump( $logchainref, j => 'AUDIT', targetopts => '--type ' . lc $target ) if $audit; add_ijump( $logchainref, g => $target ); $target = 'blacklog'; } elsif ( $audit ) { require_capability 'AUDIT_TARGET', "BLACKLIST_DISPOSITION=$disposition", 's'; $target = verify_audit( $disposition ); } } BLACKLIST: { if ( my $fn = open_file 'blacklist' ) { my $first_entry = 1; first_entry "$doing $fn..."; while ( read_a_line ) { if ( $first_entry ) { unless ( @$zones || @$zones1 ) { warning_message qq(The entries in $fn have been ignored because there are no 'blacklist' zones); close_file; last BLACKLIST; } $first_entry = 0; } my ( $networks, $protocol, $ports, $options ) = split_line 4, 'blacklist file', { networks => 0, proto => 1, port => 2, options => 3 }; if ( $options eq '-' ) { $options = 'src'; } elsif ( $options eq 'audit' ) { $options = 'audit,src'; } my ( $to, $from, $whitelist, $auditone ) = ( 0, 0, 0, 0 ); my @options = split_list $options, 'option'; for ( @options ) { $whitelist++ if $_ eq 'whitelist'; $auditone++ if $_ eq 'audit'; } warning_message "Duplicate 'whitelist' option ignored" if $whitelist > 1; my $tgt = $whitelist ? 'RETURN' : $target; if ( $auditone ) { fatal_error "'audit' not allowed in whitelist entries" if $whitelist; if ( $audit ) { warning_message "Superfluous 'audit' option ignored"; } else { warning_message "Duplicate 'audit' option ignored" if $auditone > 1; $tgt = verify_audit( 'A_' . $target, $orig_target, $target ); } } for ( @options ) { if ( $_ =~ /^(?:src|from)$/ ) { if ( $from++ ) { warning_message "Duplicate 'src' ignored"; } else { if ( @$zones ) { expand_rule( $chainref , NO_RESTRICT , do_proto( $protocol , $ports, '' ) , $networks, '', '' , $tgt , '' , $tgt , '' ); } else { warning_message '"src" entry ignored because there are no "blacklist in" zones'; } } } elsif ( $_ =~ /^(?:dst|to)$/ ) { if ( $to++ ) { warning_message "Duplicate 'dst' ignored"; } else { if ( @$zones1 ) { expand_rule( $chainref1 , NO_RESTRICT , do_proto( $protocol , $ports, '' ) , '', $networks, '' , $tgt , '' , $tgt , '' ); } else { warning_message '"dst" entry ignored because there are no "blacklist out" zones'; } } } else { fatal_error "Invalid blacklist option($_)" unless $_ eq 'whitelist' || $_ eq 'audit'; } } progress_message " \"$currentline\" added to blacklist"; } warning_message q(There are interfaces or zones with the 'blacklist' option but the 'blacklist' file is empty) if $first_entry && @$zones; } elsif ( @$zones || @$zones1 ) { warning_message q(There are interfaces or zones with the 'blacklist' option, but the 'blacklist' file is either missing or has zero size); } } } sub process_routestopped() { if ( my $fn = open_file 'routestopped' ) { my ( @allhosts, %source, %dest , %notrack, @rule ); my $seq = 0; first_entry "$doing $fn..."; while ( read_a_line ) { my ($interface, $hosts, $options , $proto, $ports, $sports ) = split_line 6, 'routestopped file', { interface => 1, hosts => 2, options => 3, proto => 4, dport => 5, sport => 6 }; my $interfaceref; fatal_error 'INTERFACE must be specified' if $interface eq '-'; fatal_error "Unknown interface ($interface)" unless $interfaceref = known_interface $interface; $hosts = ALLIP unless $hosts && $hosts ne '-'; my $routeback = 0; my @hosts; $seq++; my $rule = do_proto( $proto, $ports, $sports, 0 ); for my $host ( split /,/, $hosts ) { fatal_error "Ipsets not allowed with SAVE_IPSETS=Yes" if $host =~ /^!?\+/ && $config{SAVE_IPSETS}; validate_host $host, 1; push @hosts, "$interface|$host|$seq"; push @rule, $rule; } unless ( $options eq '-' ) { for my $option (split /,/, $options ) { if ( $option eq 'routeback' ) { if ( $routeback ) { warning_message "Duplicate 'routeback' option ignored"; } else { $routeback = 1; } } elsif ( $option eq 'source' ) { for my $host ( split /,/, $hosts ) { $source{"$interface|$host|$seq"} = 1; } } elsif ( $option eq 'dest' ) { for my $host ( split /,/, $hosts ) { $dest{"$interface|$host|$seq"} = 1; } } elsif ( $option eq 'notrack' ) { for my $host ( split /,/, $hosts ) { $notrack{"$interface|$host|$seq"} = 1; } } else { warning_message "Unknown routestopped option ( $option ) ignored" unless $option eq 'critical'; warning_message "The 'critical' option is no longer supported (or needed)"; } } } if ( $routeback || $interfaceref->{options}{routeback} ) { my $chainref = $filter_table->{FORWARD}; for my $host ( split /,/, $hosts ) { add_ijump( $chainref , j => 'ACCEPT', imatch_source_dev( $interface ) , imatch_dest_dev( $interface ) , imatch_source_net( $host ) , imatch_dest_net( $host ) ); clearrule; } } push @allhosts, @hosts; } for my $host ( @allhosts ) { my ( $interface, $h, $seq ) = split /\|/, $host; my $source = match_source_net $h; my $dest = match_dest_net $h; my $sourcei = match_source_dev $interface; my $desti = match_dest_dev $interface; my $rule = shift @rule; add_rule $filter_table->{INPUT}, "$sourcei $source $rule -j ACCEPT", 1; add_rule $filter_table->{OUTPUT}, "$desti $dest $rule -j ACCEPT", 1 unless $config{ADMINISABSENTMINDED}; my $matched = 0; if ( $source{$host} ) { add_rule $filter_table->{FORWARD}, "$sourcei $source $rule -j ACCEPT", 1; $matched = 1; } if ( $dest{$host} ) { add_rule $filter_table->{FORWARD}, "$desti $dest $rule -j ACCEPT", 1; $matched = 1; } if ( $notrack{$host} ) { add_rule $raw_table->{PREROUTING}, "$sourcei $source $rule -j NOTRACK", 1; add_rule $raw_table->{OUTPUT}, "$desti $dest $rule -j NOTRACK", 1; } unless ( $matched ) { for my $host1 ( @allhosts ) { unless ( $host eq $host1 ) { my ( $interface1, $h1 , $seq1 ) = split /\|/, $host1; my $dest1 = match_dest_net $h1; my $desti1 = match_dest_dev $interface1; add_rule $filter_table->{FORWARD}, "$sourcei $desti1 $source $dest1 $rule -j ACCEPT", 1; clearrule; } } } } } } sub setup_mss(); sub add_common_rules() { my $interface; my $chainref; my $target; my $target1; my $rule; my $list; my $chain; my $dynamicref; my @state = $config{BLACKLISTNEWONLY} ? $globals{UNTRACKED} ? state_imatch 'NEW,INVALID,UNTRACKED' : state_imatch 'NEW,INVALID' : (); my $level = $config{BLACKLIST_LOGLEVEL}; my $rejectref = $filter_table->{reject}; if ( $config{DYNAMIC_BLACKLIST} ) { add_rule_pair dont_delete( new_standard_chain( 'logdrop' ) ), '' , 'DROP' , $level ; add_rule_pair dont_delete( new_standard_chain( 'logreject' ) ), '' , 'reject' , $level ; $dynamicref = dont_optimize( new_standard_chain( 'dynamic' ) ); add_ijump $filter_table->{INPUT}, j => $dynamicref, @state; add_commands( $dynamicref, '[ -f ${VARDIR}/.dynamic ] && cat ${VARDIR}/.dynamic >&3' ); } setup_mss; add_ijump( $filter_table->{OUTPUT} , j => 'ACCEPT', state_imatch 'ESTABLISHED,RELATED' ) if ( $config{FASTACCEPT} ); my $policy = $config{SFILTER_DISPOSITION}; $level = $config{SFILTER_LOG_LEVEL}; my $audit = $policy =~ s/^A_//; my @ipsec = have_ipsec ? ( policy => '--pol none --dir in' ) : (); if ( $level || $audit ) { # # Create a chain to log and/or audit and apply the policy # $chainref = new_standard_chain 'sfilter'; log_rule $level , $chainref , $policy , '' if $level ne ''; add_ijump( $chainref, j => 'AUDIT', targetopts => '--type ' . lc $policy ) if $audit; add_ijump $chainref, g => $policy eq 'REJECT' ? 'reject' : $policy; $target = 'sfilter'; } else { $target = $policy eq 'REJECT' ? 'reject' : $policy; } if ( @ipsec ) { # # sfilter1 will be used in the FORWARD chain where we allow traffic entering the interface # to leave the interface encrypted. We need a separate chain because '--dir out' cannot be # used in the input chain # $chainref = new_standard_chain 'sfilter1'; add_ijump ( $chainref, j => 'RETURN', policy => '--pol ipsec --dir out' ); log_rule $level , $chainref , $policy , '' if $level ne ''; add_ijump( $chainref, j => 'AUDIT', targetopts => '--type ' . lc $policy ) if $audit; add_ijump $chainref, g => $policy eq 'REJECT' ? 'reject' : $policy; $target1 = 'sfilter1'; } else { # # No IPSEC -- use the same target in both INPUT and FORWARD # $target1 = $target; } for $interface ( grep $_ ne '%vserver%', all_interfaces ) { ensure_chain( 'filter', $_ ) for first_chains( $interface ), output_chain( $interface ); my $interfaceref = find_interface $interface; unless ( $interfaceref->{options}{ignore} ) { my @filters = @{$interfaceref->{filter}}; $chainref = $filter_table->{forward_chain $interface}; if ( @filters ) { add_ijump( $chainref , @ipsec ? 'j' : 'g' => $target1, imatch_source_net( $_ ), @ipsec ), $chainref->{filtered}++ for @filters; $interfaceref->{options}{use_forward_chain} = 1; } elsif ( $interfaceref->{bridge} eq $interface ) { add_ijump( $chainref , @ipsec ? 'j' : 'g' => $target1, imatch_dest_dev( $interface ), @ipsec ), $chainref->{filtered}++ unless( $config{ROUTE_FILTER} eq 'on' || $interfaceref->{options}{routeback} || $interfaceref->{options}{routefilter} || $interfaceref->{physical} eq '+' ); $interfaceref->{options}{use_forward_chain} = 1; } add_ijump( $chainref, j => 'ACCEPT', state_imatch 'ESTABLISHED,RELATED' ), $chainref->{filtered}++ if $config{FASTACCEPT}; add_ijump( $chainref, j => $dynamicref, @state ), $chainref->{filtered}++ if $dynamicref; $chainref = $filter_table->{input_chain $interface}; if ( @filters ) { add_ijump( $chainref , g => $target, imatch_source_net( $_ ), @ipsec ), $chainref->{filtered}++ for @filters; $interfaceref->{options}{use_input_chain} = 1; } add_ijump( $chainref, j => 'ACCEPT', state_imatch 'ESTABLISHED,RELATED' ), $chainref->{filtered}++ if $config{FASTACCEPT}; add_ijump( $chainref, j => $dynamicref, @state ), $chainref->{filtered}++ if $dynamicref; } } # # Delete 'sfilter' chains unless there are referenced to them # for ( qw/sfilter sfilter1/ ) { if ( $chainref = $filter_table->{$_} ) { $chainref->{referenced} = 0 unless keys %{$chainref->{references}}; } } run_user_exit1 'initdone'; setup_blacklist; $list = find_hosts_by_option 'nosmurfs'; if ( @$list ) { progress_message2 'Adding Anti-smurf Rules'; $chainref = new_standard_chain 'smurfs'; my $smurfdest = $config{SMURF_DISPOSITION}; if ( supplied $config{SMURF_LOG_LEVEL} ) { my $smurfref = new_chain( 'filter', 'smurflog' ); log_rule_limit( $config{SMURF_LOG_LEVEL}, $smurfref, 'smurfs' , 'DROP', $globals{LOGLIMIT}, '', 'add', '' ); add_ijump( $smurfref, j => 'AUDIT', targetopts => '--type drop' ) if $smurfdest eq 'A_DROP'; add_ijump( $smurfref, j => 'DROP' ); $smurfdest = 'smurflog'; } else { verify_audit( $smurfdest ) if $smurfdest eq 'A_DROP'; } if ( have_capability( 'ADDRTYPE' ) ) { if ( $family == F_IPV4 ) { add_ijump $chainref , j => 'RETURN', s => '0.0.0.0'; ; } else { add_ijump $chainref , j => 'RETURN', s => '::'; } add_ijump( $chainref, g => $smurfdest, addrtype => '--src-type BROADCAST' ) ; } else { if ( $family == F_IPV4 ) { add_commands $chainref, 'for address in $ALL_BCASTS; do'; } else { add_commands $chainref, 'for address in $ALL_ACASTS; do'; } incr_cmd_level $chainref; add_ijump( $chainref, g => $smurfdest, s => '$address' ); decr_cmd_level $chainref; add_commands $chainref, 'done'; } if ( $family == F_IPV4 ) { add_ijump( $chainref, g => $smurfdest, s => '224.0.0.0/4' ); } else { add_ijump( $chainref, g => $smurfdest, s => IPv6_MULTICAST ); } my @state = $globals{UNTRACKED} ? state_imatch 'NEW,INVALID,UNTRACKED' : state_imatch 'NEW,INVALID'; for my $hostref ( @$list ) { $interface = $hostref->[0]; my $ipsec = $hostref->[1]; my @policy = have_ipsec ? ( policy => "--pol $ipsec --dir in" ) : (); my $target = source_exclusion( $hostref->[3], $chainref ); for $chain ( first_chains $interface ) { add_ijump( $filter_table->{$chain} , j => $target, @state, imatch_source_net( $hostref->[2] ), @policy ); } set_interface_option $interface, 'use_input_chain', 1; set_interface_option $interface, 'use_forward_chain', 1; } } if ( have_capability( 'ADDRTYPE' ) ) { add_ijump $rejectref , j => 'DROP' , addrtype => '--src-type BROADCAST'; } else { if ( $family == F_IPV4 ) { add_commands $rejectref, 'for address in $ALL_BCASTS; do'; } else { add_commands $rejectref, 'for address in $ALL_ACASTS; do'; } incr_cmd_level $rejectref; add_ijump $rejectref, j => 'DROP', d => '$address'; decr_cmd_level $rejectref; add_commands $rejectref, 'done'; } if ( $family == F_IPV4 ) { add_ijump $rejectref , j => 'DROP', s => '224.0.0.0/4'; } else { add_ijump $rejectref , j => 'DROP', s => IPv6_MULTICAST; } add_ijump $rejectref , j => 'DROP', p => 2; add_ijump $rejectref , j => 'REJECT', targetopts => '--reject-with tcp-reset', p => 6; if ( have_capability( 'ENHANCED_REJECT' ) ) { add_ijump $rejectref , j => 'REJECT', p => 17; if ( $family == F_IPV4 ) { add_ijump $rejectref, j => 'REJECT --reject-with icmp-host-unreachable', p => 1; add_ijump $rejectref, j => 'REJECT --reject-with icmp-host-prohibited'; } else { add_ijump $rejectref, j => 'REJECT --reject-with icmp6-addr-unreachable', p => 58; add_ijump $rejectref, j => 'REJECT --reject-with icmp6-adm-prohibited'; } } else { add_ijump $rejectref , j => 'REJECT'; } $list = find_interfaces_by_option 'dhcp'; if ( @$list ) { progress_message2 'Adding rules for DHCP'; my $ports = $family == F_IPV4 ? '67:68' : '546:547'; for $interface ( @$list ) { set_interface_option $interface, 'use_input_chain', 1; set_interface_option $interface, 'use_forward_chain', 1; set_rule_option( add_ijump( $filter_table->{$_} , j => 'ACCEPT', p => "udp --dport $ports" ) , 'dhcp', 1 ) for input_chain( $interface ), output_chain( $interface ); add_ijump( $filter_table->{forward_chain $interface} , j => 'ACCEPT', p => "udp --dport $ports" , imatch_dest_dev( $interface ) ) if get_interface_option( $interface, 'bridge' ); } } $list = find_hosts_by_option 'tcpflags'; if ( @$list ) { my $level = $config{TCP_FLAGS_LOG_LEVEL}; my $disposition = $config{TCP_FLAGS_DISPOSITION}; my $audit = $disposition =~ /^A_/; progress_message2 "$doing TCP Flags filtering..."; $chainref = new_standard_chain 'tcpflags'; if ( $level ) { my $logflagsref = new_standard_chain 'logflags'; my $savelogparms = $globals{LOGPARMS}; $globals{LOGPARMS} = "$globals{LOGPARMS}--log-ip-options "; log_rule $level , $logflagsref , $config{TCP_FLAGS_DISPOSITION}, ''; $globals{LOGPARMS} = $savelogparms; if ( $audit ) { $disposition =~ s/^A_//; add_ijump( $logflagsref, j => 'AUDIT', targetopts => '--type ' . lc $disposition ); } if ( $disposition eq 'REJECT' ) { add_ijump $logflagsref , j => 'REJECT', targetopts => '--reject-with tcp-reset', p => 6; } else { add_ijump $logflagsref , j => $disposition; } $disposition = 'logflags'; } elsif ( $audit ) { require_capability( 'AUDIT_TARGET', "TCP_FLAGS_DISPOSITION=$disposition", 's' ); verify_audit( $disposition ); } add_ijump $chainref , g => $disposition, p => 'tcp --tcp-flags ALL FIN,URG,PSH'; add_ijump $chainref , g => $disposition, p => 'tcp --tcp-flags ALL NONE'; add_ijump $chainref , g => $disposition, p => 'tcp --tcp-flags SYN,RST SYN,RST'; add_ijump $chainref , g => $disposition, p => 'tcp --tcp-flags SYN,FIN SYN,FIN'; add_ijump $chainref , g => $disposition, p => 'tcp --syn --sport 0'; for my $hostref ( @$list ) { my $interface = $hostref->[0]; my $target = source_exclusion( $hostref->[3], $chainref ); my @policy = have_ipsec ? ( policy => "--pol $hostref->[1] --dir in" ) : (); for $chain ( first_chains $interface ) { add_ijump( $filter_table->{$chain} , j => $target, p => 'tcp', imatch_source_net( $hostref->[2] ), @policy ); } set_interface_option $interface, 'use_input_chain', 1; set_interface_option $interface, 'use_forward_chain', 1; } } if ( $family == F_IPV4 ) { my $announced = 0; $list = find_interfaces_by_option 'upnp'; if ( @$list ) { progress_message2 "$doing UPnP"; $chainref = dont_optimize new_nat_chain( 'UPnP' ); add_commands( $chainref, '[ -s /${VARDIR}/.UPnP ] && cat ${VARDIR}/.UPnP >&3' ); $announced = 1; for $interface ( @$list ) { add_ijump $nat_table->{PREROUTING} , j => 'UPnP', imatch_source_dev ( $interface ); } } $list = find_interfaces_by_option 'upnpclient'; if ( @$list ) { progress_message2 "$doing UPnP" unless $announced; for $interface ( @$list ) { my $chainref = $filter_table->{input_chain $interface}; my $base = uc chain_base get_physical $interface; my $variable = get_interface_gateway $interface; if ( interface_is_optional $interface ) { add_commands( $chainref, qq(if [ -n "SW_\$${base}_IS_USABLE" -a -n "$variable" ]; then) ); incr_cmd_level( $chainref ); add_ijump( $chainref, j => 'ACCEPT', imatch_source_dev( $interface ), s => $variable, p => 'udp' ); decr_cmd_level( $chainref ); add_commands( $chainref, 'fi' ); } else { add_ijump( $chainref, j => 'ACCEPT', imatch_source_dev( $interface ), s => $variable, p => 'udp' ); } } } } setup_syn_flood_chains; } my %maclist_targets = ( ACCEPT => { target => 'RETURN' , mangle => 1 } , REJECT => { target => 'reject' , mangle => 0 } , DROP => { target => 'DROP' , mangle => 1 } ); sub setup_mac_lists( $ ) { my $phase = $_[0]; my %maclist_interfaces; my $table = $config{MACLIST_TABLE}; my $maclist_hosts = find_hosts_by_option 'maclist'; my $target = $globals{MACLIST_TARGET}; my $level = $config{MACLIST_LOG_LEVEL}; my $disposition = $config{MACLIST_DISPOSITION}; my $audit = $disposition =~ /^A_/; my $ttl = $config{MACLIST_TTL}; progress_message2 "$doing MAC Filtration -- Phase $phase..."; for my $hostref ( @$maclist_hosts ) { $maclist_interfaces{ $hostref->[0] } = 1; } my @maclist_interfaces = ( sort keys %maclist_interfaces ); if ( $phase == 1 ) { for my $interface ( @maclist_interfaces ) { my $chainref = new_chain $table , mac_chain $interface; if ( $family == F_IPV4 ) { add_ijump $chainref , j => 'RETURN', s => '0.0.0.0', d => '255.255.255.255', p => 'udp --dport 67:68' if $table eq 'mangle' && get_interface_option( $interface, 'dhcp'); } else { # # Accept any packet with a link-level source or destination address # add_ijump $chainref , j => 'RETURN', s => 'ff80::/10'; add_ijump $chainref , j => 'RETURN', d => 'ff80::/10'; # # Accept Multicast # add_ijump $chainref , j => 'RETURN', d => IPv6_MULTICAST; } if ( $ttl ) { my $chain1ref = new_chain $table, macrecent_target $interface; my $chain = $chainref->{name}; add_ijump $chainref, j => 'RETURN', recent => "--rcheck --seconds $ttl --name $chain"; add_ijump $chainref, j => $chain1ref; add_ijump $chainref, j => 'RETURN', recent => "--update --name $chain"; add_irule $chainref, recent => "--set --name $chain"; } } if ( my $fn = open_file 'maclist' ) { first_entry "$doing $fn..."; while ( read_a_line ) { my ( $original_disposition, $interface, $mac, $addresses ) = split_line1 4, 'maclist file', { disposition => 0, interface => 1, mac => 2, addresses => 3 }; if ( $original_disposition eq 'COMMENT' ) { process_comment; } else { my ( $disposition, $level, $remainder) = split( /:/, $original_disposition, 3 ); fatal_error "Invalid DISPOSITION ($original_disposition)" if defined $remainder || ! $disposition; my $targetref = $maclist_targets{$disposition}; fatal_error "Invalid DISPOSITION ($original_disposition)" if ! $targetref || ( ( $table eq 'mangle' ) && ! $targetref->{mangle} ); fatal_error "Unknown Interface ($interface)" unless known_interface( $interface ); fatal_error "No hosts on $interface have the maclist option specified" unless $maclist_interfaces{$interface}; my $chainref = $chain_table{$table}{( $ttl ? macrecent_target $interface : mac_chain $interface )}; $mac = '' unless $mac && ( $mac ne '-' ); $addresses = '' unless defined $addresses && ( $addresses ne '-' ); fatal_error "You must specify a MAC address or an IP address" unless $mac || $addresses; $mac = do_mac $mac if $mac; if ( $addresses ) { for my $address ( split ',', $addresses ) { my $source = match_source_net $address; log_rule_limit $level, $chainref , mac_chain( $interface) , $disposition, '', '', 'add' , "${mac}${source}" if supplied $level; add_ijump( $chainref , j => 'AUDIT', targetopts => '--type ' . lc $disposition ) if $audit && $disposition ne 'ACCEPT'; add_jump( $chainref , $targetref->{target}, 0, "${mac}${source}" ); } } else { log_rule_limit $level, $chainref , mac_chain( $interface) , $disposition, '', '', 'add' , $mac if supplied $level; add_ijump( $chainref , j => 'AUDIT', targetopts => '--type ' . lc $disposition ) if $audit && $disposition ne 'ACCEPT'; add_jump ( $chainref , $targetref->{target}, 0, "$mac" ); } progress_message " Maclist entry \"$currentline\" $done"; } } clear_comment; } # # Generate jumps from the input and forward chains # for my $hostref ( @$maclist_hosts ) { my $interface = $hostref->[0]; my $ipsec = $hostref->[1]; my @policy = have_ipsec ? ( policy => "--pol $ipsec --dir in" ) : (); my @source = imatch_source_net $hostref->[2]; my @state = $globals{UNTRACKED} ? state_imatch 'NEW,UNTRACKED' : state_imatch 'NEW'; if ( $table eq 'filter' ) { my $chainref = source_exclusion( $hostref->[3], $filter_table->{mac_chain $interface} ); for my $chain ( first_chains $interface ) { add_ijump $filter_table->{$chain} , j => $chainref, @source, @state, @policy; } set_interface_option $interface, 'use_input_chain', 1; set_interface_option $interface, 'use_forward_chain', 1; } else { my $chainref = source_exclusion( $hostref->[3], $mangle_table->{mac_chain $interface} ); add_ijump $mangle_table->{PREROUTING}, j => $chainref, imatch_source_dev( $interface ), @source, @state, @policy; } } } else { # # Phase II # for my $interface ( @maclist_interfaces ) { my $chainref = $chain_table{$table}{( $ttl ? macrecent_target $interface : mac_chain $interface )}; my $chain = $chainref->{name}; if ( $family == F_IPV4 ) { if ( $level ne '' || $disposition ne 'ACCEPT' ) { my $variable = get_interface_addresses source_port_to_bridge( $interface ); if ( have_capability( 'ADDRTYPE' ) ) { add_commands( $chainref, "for address in $variable; do" ); incr_cmd_level( $chainref ); add_ijump( $chainref, j => 'RETURN', s => '$address', addrtype => '--dst-type BROADCAST' ); add_ijump( $chainref, j => 'RETURN', s => '$address', d => '224.0.0.0/4' ); decr_cmd_level( $chainref ); add_commands( $chainref, 'done' ); } else { my $bridge = source_port_to_bridge( $interface ); my $bridgeref = find_interface( $bridge ); add_commands( $chainref, "for address in $variable; do" ); incr_cmd_level( $chainref ); if ( $bridgeref->{broadcasts} ) { for my $address ( @{$bridgeref->{broadcasts}}, '255.255.255.255' ) { add_ijump( $chainref, j => 'RETURN', s => '$address', d => $address ); } } else { my $variable1 = get_interface_bcasts $bridge; add_commands( $chainref, " for address1 in $variable1; do" ); incr_cmd_level( $chainref ); add_ijump( $chainref, j => 'RETURN', s => '$address', d => '$address1' ); decr_cmd_level( $chainref ); add_commands( $chainref, 'done' ); } add_ijump( $chainref, j => 'RETURN', s => '$address', d => '224.0.0.0/4' ); decr_cmd_level( $chainref ); add_commands( $chainref, 'done' ); } } } run_user_exit2( 'maclog', $chainref ); log_rule_limit $level, $chainref , $chain , $disposition, '', '', 'add', '' if $level ne ''; add_ijump $chainref, j => $target; } } } # # Helper functions for generate_matrix() #----------------------------------------- # # Return the target for rules from $zone to $zone1. # sub rules_target( $$ ) { my ( $zone, $zone1 ) = @_; my $chain = rules_chain( ${zone}, ${zone1} ); my $chainref = $filter_table->{$chain}; return $chain if $chainref && $chainref->{referenced}; return 'ACCEPT' if $zone eq $zone1; assert( $chainref ); if ( $chainref->{policy} ne 'CONTINUE' ) { my $policyref = $filter_table->{$chainref->{policychain}}; assert( $policyref ); return $policyref->{name} if $policyref ne $chainref; return $chainref->{policy} eq 'REJECT' ? 'reject' : $chainref->{policy}; } ''; # CONTINUE policy } # # Generate rules for one destination zone # sub generate_dest_rules( $$$;@ ) { my ( $chainref, $chain, $z2, @matches ) = @_; my $z2ref = find_zone( $z2 ); my $type2 = $z2ref->{type}; if ( $type2 == VSERVER ) { for my $hostref ( @{$z2ref->{hosts}{ip}{'%vserver%'}} ) { my $exclusion = dest_exclusion( $hostref->{exclusions}, $chain); for my $net ( @{$hostref->{hosts}} ) { add_ijump( $chainref, j => $exclusion , imatch_dest_net ( $net ), @matches ); } } } else { add_ijump( $chainref, j => $chain, @matches ); } } # # Generate rules for one vserver source zone # sub generate_source_rules( $$$;@ ) { my ( $outchainref, $z1, $z2, @matches ) = @_; my $chain = rules_target ( $z1, $z2 ); if ( $chain ) { # # Not a CONTINUE policy with no rules # for my $hostref ( @{defined_zone( $z1 )->{hosts}{ip}{'%vserver%'}} ) { my @ipsec_match = match_ipsec_in $z1 , $hostref; my $exclusion = source_exclusion( $hostref->{exclusions}, $chain); for my $net ( @{$hostref->{hosts}} ) { generate_dest_rules( $outchainref, $exclusion, $z2, imatch_source_net( $net ), @matches , @ipsec_match ); } } } } # # Loopback traffic -- this is where we assemble the intra-firewall chains # sub handle_loopback_traffic() { my @zones = ( vserver_zones, firewall_zone ); my $natout = $nat_table->{OUTPUT}; my $rulenum = 0; my $outchainref; my @rule; if ( @zones > 1 ) { $outchainref = new_standard_chain 'loopback'; add_ijump $filter_table->{OUTPUT}, j => $outchainref, o => 'lo'; } else { $outchainref = $filter_table->{OUTPUT}; @rule = ( o => 'lo'); } for my $z1 ( @zones ) { my $z1ref = find_zone( $z1 ); my $type1 = $z1ref->{type}; my $natref = $nat_table->{dnat_chain $z1}; if ( $type1 == FIREWALL ) { for my $z2 ( @zones ) { my $chain = rules_target( $z1, $z2 ); generate_dest_rules( $outchainref, $chain, $z2, @rule ) if $chain; } } else { for my $z2 ( @zones ) { generate_source_rules( $outchainref, $z1, $z2, @rule ); } } if ( $natref && $natref->{referenced} ) { my $source_hosts_ref = defined_zone( $z1 )->{hosts}; for my $typeref ( values %{$source_hosts_ref} ) { for my $hostref ( @{$typeref->{'%vserver%'}} ) { my $exclusion = source_exclusion( $hostref->{exclusions}, $natref); for my $net ( @{$hostref->{hosts}} ) { insert_ijump( $natout, j => $exclusion, $rulenum++, imatch_source_net( $net , 0, ) ); } } } } } add_ijump $filter_table->{INPUT} , j => 'ACCEPT', i => 'lo'; } # # Add jumps from the builtin chains to the interface-chains that are used by this configuration # sub add_interface_jumps { our %input_jump_added; our %output_jump_added; our %forward_jump_added; # # Add Nat jumps # for my $interface ( @_ ) { addnatjump 'POSTROUTING' , snat_chain( $interface ), imatch_dest_dev( $interface ); } addnatjump 'PREROUTING' , 'nat_in'; addnatjump 'POSTROUTING' , 'nat_out'; addnatjump 'PREROUTING', 'dnat'; for my $interface ( grep $_ ne '%vserver%', @_ ) { addnatjump 'PREROUTING' , input_chain( $interface ) , imatch_source_dev( $interface ); addnatjump 'POSTROUTING' , output_chain( $interface ) , imatch_dest_dev( $interface ); addnatjump 'POSTROUTING' , masq_chain( $interface ) , imatch_dest_dev( $interface ); if ( have_capability 'RAWPOST_TABLE' ) { insert_ijump ( $rawpost_table->{POSTROUTING}, j => postrouting_chain( $interface ), 0, imatch_dest_dev( $interface) ) if $rawpost_table->{postrouting_chain $interface}; insert_ijump ( $raw_table->{PREROUTING}, j => prerouting_chain( $interface ), 0, imatch_source_dev( $interface) ) if $raw_table->{prerouting_chain $interface}; insert_ijump ( $raw_table->{OUTPUT}, j => output_chain( $interface ), 0, imatch_dest_dev( $interface) ) if $raw_table->{output_chain $interface}; } } # # Add the jumps to the interface chains from filter FORWARD, INPUT, OUTPUT # for my $interface ( grep $_ ne '%vserver%', @_ ) { my $forwardref = $filter_table->{forward_chain $interface}; my $inputref = $filter_table->{input_chain $interface}; my $outputref = $filter_table->{output_chain $interface}; my $interfaceref = find_interface($interface); if ( $interfaceref->{options}{port} ) { my $bridge = $interfaceref->{bridge}; add_ijump ( $filter_table->{forward_chain $bridge}, j => 'ACCEPT', imatch_source_dev( $interface, 1), imatch_dest_dev( $interface, 1) ) unless $interfaceref->{nets} || ! $interfaceref->{options}{bridge}; add_ijump( $filter_table->{forward_chain $bridge} , j => $forwardref , imatch_source_dev( $interface, 1 ) ) unless $forward_jump_added{$interface} || ! use_forward_chain $interface, $forwardref; add_ijump( $filter_table->{input_chain $bridge }, j => $inputref , imatch_source_dev( $interface, 1 ) ) unless $input_jump_added{$interface} || ! use_input_chain $interface, $inputref; unless ( $output_jump_added{$interface} || ! use_output_chain $interface, $outputref ) { add_ijump( $filter_table->{output_chain $bridge} , j => $outputref , imatch_dest_dev( $interface, 1 ) ) unless get_interface_option( $interface, 'port' ); } } else { add_ijump ( $filter_table->{FORWARD}, j => 'ACCEPT', imatch_source_dev( $interface) , imatch_dest_dev( $interface) ) unless $interfaceref->{nets} || ! $interfaceref->{options}{bridge}; add_ijump( $filter_table->{FORWARD} , j => $forwardref , imatch_source_dev( $interface ) ) unless $forward_jump_added{$interface} || ! use_forward_chain $interface, $forwardref; add_ijump( $filter_table->{INPUT} , j => $inputref , imatch_source_dev( $interface ) ) unless $input_jump_added{$interface} || ! use_input_chain $interface, $inputref; unless ( $output_jump_added{$interface} || ! use_output_chain $interface, $outputref ) { add_ijump $filter_table->{OUTPUT} , j => $outputref , imatch_dest_dev( $interface ) unless get_interface_option( $interface, 'port' ); } } } handle_loopback_traffic; } # Generate the rules matrix. # # Stealing a comment from the Burroughs B6700 MCP Operating System source, "generate_matrix makes a sow's ear out of a silk purse". # # The biggest disadvantage of the zone-policy-rule model used by Shorewall is that it doesn't scale well as the number of zones increases (Order N**2 where N = number of zones). # A major goal of the rewrite of the compiler in Perl was to restrict those scaling effects to this function and the rules that it generates. # # The function traverses the full "source-zone by destination-zone" matrix and generates the rules necessary to direct traffic through the right set of filter-table and # nat-table rules. # sub generate_matrix() { my @interfaces = ( all_interfaces ); # # Should this be the real PREROUTING chain? # my $preroutingref = ensure_chain 'nat', 'dnat'; my $fw = firewall_zone; my @zones = off_firewall_zones; my @vservers = vserver_zones; my $notrackref = $raw_table->{notrack_chain $fw}; my @state = $config{BLACKLISTNEWONLY} ? $globals{UNTRACKED} ? state_imatch 'NEW,INVALID,UNTRACKED' : state_imatch 'NEW,INVALID' : (); my $interface_jumps_added = 0; our %input_jump_added = (); our %output_jump_added = (); our %forward_jump_added = (); my %ipsec_jump_added = (); progress_message2 'Generating Rule Matrix...'; progress_message ' Handling blacklisting and complex zones...'; # # Special processing for complex and/or blacklisting configurations # for my $zone ( @zones ) { my $zoneref = find_zone( $zone ); my $simple = @zones <= 2 && ! $zoneref->{options}{complex}; # # Handle blacklisting first # if ( $zoneref->{options}{in}{blacklist} ) { my $blackref = $filter_table->{blacklst}; insert_ijump ensure_rules_chain( rules_chain( $zone, $_ ) ) , j => $blackref , -1, @state for firewall_zone, @vservers; if ( $simple ) { # # We won't create a zone forwarding chain for this zone so we must add blacklisting jumps to the rules chains # for my $zone1 ( @zones ) { my $ruleschain = rules_chain( $zone, $zone1 ); my $ruleschainref = $filter_table->{$ruleschain}; if ( ( $zone ne $zone1 || $ruleschainref->{referenced} ) && $ruleschainref->{policy} ne 'NONE' ) { insert_ijump( ensure_rules_chain( $ruleschain ), j => $blackref, -1, @state ); } } } } if ( $zoneref->{options}{out}{blacklist} ) { my $blackref = $filter_table->{blackout}; insert_ijump ensure_rules_chain( rules_chain( firewall_zone, $zone ) ) , j => $blackref , -1, @state; for my $zone1 ( @zones, @vservers ) { my $ruleschain = rules_chain( $zone1, $zone ); my $ruleschainref = $filter_table->{$ruleschain}; if ( ( $zone ne $zone1 || $ruleschainref->{referenced} ) && $ruleschainref->{policy} ne 'NONE' ) { insert_ijump( ensure_rules_chain( $ruleschain ), j => $blackref, -1, @state ); } } } next if $simple; # # Complex zone or we have more than one non-firewall zone -- create a zone forwarding chain # my $frwd_ref = new_standard_chain zone_forward_chain( $zone ); insert_ijump $frwd_ref , j => $filter_table->{blacklst}, -1, @state if $zoneref->{options}{in}{blacklist}; if ( have_ipsec ) { # # Because policy match only matches an 'in' or an 'out' policy (but not both), we have to place the # '--pol ipsec --dir in' rules at the front of the (interface) forwarding chains. Otherwise, decrypted packets # can match '--pol none --dir out' rules and send the packets down the wrong rules chain. # my $type = $zoneref->{type}; my $source_ref = ( $zoneref->{hosts}{ipsec} ) || {}; for my $interface ( sort { interface_number( $a ) <=> interface_number( $b ) } keys %$source_ref ) { my $sourcechainref = $filter_table->{forward_chain $interface}; my @interfacematch; my $interfaceref = find_interface $interface; if ( use_forward_chain( $interface, $sourcechainref ) ) { if ( $interfaceref->{ports} && $interfaceref->{options}{bridge} ) { @interfacematch = imatch_source_dev $interface; copy_rules( $sourcechainref, $frwd_ref, 1 ) unless $ipsec_jump_added{$zone}++; $sourcechainref = $filter_table->{FORWARD}; } elsif ( $interfaceref->{options}{port} ) { add_ijump( $filter_table->{ forward_chain $interfaceref->{bridge} } , j => $sourcechainref , imatch_source_dev( $interface , 1 ) ) unless $forward_jump_added{$interface}++; } else { add_ijump $filter_table->{FORWARD} , j => $sourcechainref, imatch_source_dev( $interface ) unless $forward_jump_added{$interface}++; } } else { if ( $interfaceref->{options}{port} ) { $sourcechainref = $filter_table->{ forward_chain $interfaceref->{bridge} }; @interfacematch = imatch_source_dev $interface, 1; } else { $sourcechainref = $filter_table->{FORWARD}; @interfacematch = imatch_source_dev $interface; } move_rules( $filter_table->{forward_chain $interface} , $frwd_ref ); } my $arrayref = $source_ref->{$interface}; for my $hostref ( @{$arrayref} ) { my @ipsec_match = match_ipsec_in $zone , $hostref; for my $net ( @{$hostref->{hosts}} ) { add_ijump( $sourcechainref, @{$zoneref->{parents}} ? 'j' : 'g' => source_exclusion( $hostref->{exclusions}, $frwd_ref ), @interfacematch , imatch_source_net( $net ), @ipsec_match ); } } } } } # # NOTRACK from firewall # add_ijump $raw_table->{OUTPUT}, j => $notrackref if $notrackref->{referenced}; # # Main source-zone matrix-generation loop # progress_message ' Entering main matrix-generation loop...'; for my $zone ( @zones ) { my $zoneref = find_zone( $zone ); my $source_hosts_ref = $zoneref->{hosts}; my $chain1 = rules_target firewall_zone , $zone; my $chain2 = rules_target $zone, firewall_zone; my $complex = $zoneref->{options}{complex} || 0; my $type = $zoneref->{type}; my $frwd_ref = $filter_table->{zone_forward_chain $zone}; my $chain = 0; my $dnatref = ensure_chain 'nat' , dnat_chain( $zone ); my $notrackref = ensure_chain 'raw' , notrack_chain( $zone ); my $nested = $zoneref->{options}{nested}; my $parenthasnat = 0; my $parenthasnotrack = 0; if ( $nested ) { # # This is a sub-zone. We need to determine if # # a) A parent zone defines DNAT/REDIRECT or notrack rules; and # b) The current zone has a CONTINUE policy to some other zone. # # If a) but not b), then we must avoid sending packets from this # zone through the DNAT/REDIRECT or notrack chain for the parent. # for my $parent ( @{$zoneref->{parents}} ) { my $ref1 = $nat_table->{dnat_chain $parent} || {}; my $ref2 = $raw_table->{notrack_chain $parent} || {}; $parenthasnat = 1 if $ref1->{referenced}; $parenthasnotrack = 1 if $ref2->{referenced}; last if $parenthasnat && $parenthasnotrack; } if ( $parenthasnat || $parenthasnotrack ) { for my $zone1 ( all_zones ) { if ( $filter_table->{rules_chain( ${zone}, ${zone1} )}->{policy} eq 'CONTINUE' ) { # # This zone has a continue policy to another zone. We must # send packets from this zone through the parent's DNAT/REDIRECT/NOTRACK chain. # $nested = 0; last; } } } else { # # No parent has DNAT or notrack so there is nothing to worry about. Don't bother to generate needless RETURN rules in the 'dnat' or 'notrack' chain. # $nested = 0; } } # # Take care of PREROUTING, INPUT and OUTPUT jumps # for my $typeref ( values %$source_hosts_ref ) { for my $interface ( sort { interface_number( $a ) <=> interface_number( $b ) } keys %$typeref ) { my $arrayref = $typeref->{$interface}; my $interfaceref = find_interface $interface; my $isport = $interfaceref->{options}{port}; my $bridge = $interfaceref->{bridge}; if ( get_physical( $interface ) eq '+' ) { # # Insert the interface-specific jumps before this one which is not interface-specific # add_interface_jumps(@interfaces) unless $interface_jumps_added++; } for my $hostref ( @$arrayref ) { my @ipsec_in_match = match_ipsec_in $zone , $hostref; my @ipsec_out_match = match_ipsec_out $zone , $hostref; my $exclusions = $hostref->{exclusions}; for my $net ( @{$hostref->{hosts}} ) { my @dest = imatch_dest_net $net; if ( $chain1 && zone_type ( $zone) != BPORT ) { my $chain1ref = $filter_table->{$chain1}; my $nextchain = dest_exclusion( $exclusions, $chain1 ); my $outputref; my $interfacechainref = $filter_table->{output_chain $interface}; my @interfacematch; my $use_output = 0; if ( @vservers || use_output_chain( $interface, $interfacechainref ) || ( @{$interfacechainref->{rules}} && ! $chain1ref ) ) { $outputref = $interfacechainref; if ( $isport ) { add_ijump( $filter_table->{ output_chain $bridge }, j => $outputref , imatch_dest_dev( $interface, 1 ) ) unless $output_jump_added{$interface}++; } else { add_ijump $filter_table->{OUTPUT}, j => $outputref, imatch_dest_dev( $interface ) unless $output_jump_added{$interface}++; } $use_output = 1; unless ( lc $net eq IPv6_LINKLOCAL ) { for my $vzone ( vserver_zones ) { generate_source_rules ( $outputref, $vzone, $zone, @dest ); } } } elsif ( $isport ) { $outputref = $filter_table->{ output_chain $bridge }; @interfacematch = imatch_dest_dev $interface, 1; } else { $outputref = $filter_table->{OUTPUT}; @interfacematch = imatch_dest_dev $interface; } add_ijump $outputref , j => $nextchain, @interfacematch, @dest, @ipsec_out_match; add_ijump( $outputref , j => $nextchain, @interfacematch, d => '255.255.255.255' , @ipsec_out_match ) if $family == F_IPV4 && $hostref->{options}{broadcast}; move_rules( $interfacechainref , $chain1ref ) unless $use_output; } clearrule; next if $hostref->{options}{destonly}; my @source = imatch_source_net $net; if ( $dnatref->{referenced} ) { # # There are DNAT/REDIRECT rules with this zone as the source. # Add a jump from this source network to this zone's DNAT/REDIRECT chain # add_ijump( $preroutingref, j => source_exclusion( $exclusions, $dnatref), imatch_source_dev( $interface), @source, @ipsec_in_match ); if ( get_physical( $interface ) eq '+' ) { # # The jump from the PREROUTING chain to dnat may not have been added above # addnatjump 'PREROUTING', 'dnat' unless $preroutingref->{references}{PREROUTING}; } check_optimization( $dnatref ) if @source; } if ( $notrackref->{referenced} ) { # # There are notrack rules with this zone as the source. # Add a jump from this source network to this zone's notrack chain # add_ijump $raw_table->{PREROUTING}, j => source_exclusion( $exclusions, $notrackref), imatch_source_dev( $interface), @source, @ipsec_in_match; } # # If this zone has parents with DNAT/REDIRECT or notrack rules and there are no CONTINUE polcies with this zone as the source # then add a RETURN jump for this source network. # if ( $nested ) { add_ijump $preroutingref, j => 'RETURN', imatch_source_dev( $interface), @source, @ipsec_in_match if $parenthasnat; add_ijump $raw_table->{PREROUTING}, j => 'RETURN', imatch_source_dev( $interface), @source, @ipsec_in_match if $parenthasnotrack; } my $chain2ref = $filter_table->{$chain2}; my $inputchainref; my $interfacechainref = $filter_table->{input_chain $interface}; my @interfacematch; my $use_input; my $blacklist = $zoneref->{options}{in}{blacklist}; if ( @vservers || use_input_chain( $interface, $interfacechainref ) || ! $chain2 || ( @{$interfacechainref->{rules}} && ! $chain2ref ) ) { $inputchainref = $interfacechainref; if ( $isport ) { add_ijump( $filter_table->{ input_chain $bridge }, j => $inputchainref , imatch_source_dev($interface, 1) ) unless $input_jump_added{$interface}++; } else { add_ijump $filter_table->{INPUT}, j => $inputchainref, imatch_source_dev($interface) unless $input_jump_added{$interface}++; } $use_input = 1; unless ( lc $net eq IPv6_LINKLOCAL ) { for my $vzone ( @vservers ) { my $target = rules_target( $zone, $vzone ); generate_dest_rules( $inputchainref, $target, $vzone, @source, @ipsec_in_match ) if $target; } } } elsif ( $isport ) { $inputchainref = $filter_table->{ input_chain $bridge }; @interfacematch = imatch_source_dev $interface, 1; } else { $inputchainref = $filter_table->{INPUT}; @interfacematch = imatch_source_dev $interface; } if ( $chain2 ) { add_ijump $inputchainref, j => source_exclusion( $exclusions, $chain2 ), @interfacematch, @source, @ipsec_in_match; move_rules( $interfacechainref , $chain2ref ) unless $use_input; } if ( $frwd_ref && $hostref->{ipsec} ne 'ipsec' ) { my $ref = source_exclusion( $exclusions, $frwd_ref ); my $forwardref = $filter_table->{forward_chain $interface}; if ( use_forward_chain $interface, $forwardref ) { add_ijump $forwardref , j => $ref, @source, @ipsec_in_match; if ( $isport ) { add_ijump( $filter_table->{ forward_chain $bridge } , j => $forwardref , imatch_source_dev( $interface , 1 ) ) unless $forward_jump_added{$interface}++; } else { add_ijump $filter_table->{FORWARD} , j => $forwardref, imatch_source_dev( $interface ) unless $forward_jump_added{$interface}++; } } else { if ( $isport ) { add_ijump( $filter_table->{ forward_chain $bridge } , j => $ref , imatch_source_dev( $interface, 1 ) , @source, @ipsec_in_match ); } else { add_ijump $filter_table->{FORWARD} , j => $ref, imatch_source_dev( $interface ) , @source, @ipsec_in_match; } move_rules ( $forwardref , $frwd_ref ); } } } } } } # # F O R W A R D I N G # my @dest_zones; my $last_chain = ''; if ( $config{OPTIMIZE} & 1 ) { my @temp_zones; for my $zone1 ( @zones ) { my $zone1ref = find_zone( $zone1 ); my $policy = $filter_table->{rules_chain( ${zone}, ${zone1} )}->{policy}; next if $policy eq 'NONE'; my $chain = rules_target $zone, $zone1; next unless $chain; if ( $zone eq $zone1 ) { next if ( scalar ( keys( %{ $zoneref->{interfaces}} ) ) < 2 ) && ! $zoneref->{options}{in_out}{routeback}; } if ( $zone1ref->{type} == BPORT ) { next unless $zoneref->{bridge} eq $zone1ref->{bridge}; } if ( $chain =~ /(2all|-all)$/ ) { if ( $chain ne $last_chain ) { $last_chain = $chain; push @dest_zones, @temp_zones; @temp_zones = ( $zone1 ); } elsif ( $policy eq 'ACCEPT' ) { push @temp_zones , $zone1; } else { $last_chain = $chain; @temp_zones = ( $zone1 ); } } else { push @dest_zones, @temp_zones, $zone1; @temp_zones = (); $last_chain = ''; } } if ( $last_chain && @temp_zones == 1 ) { push @dest_zones, @temp_zones; $last_chain = ''; } } else { @dest_zones = @zones ; } # # Here it is -- THE BIG UGLY!!!!!!!!!!!! # # We now loop through the destination zones creating jumps to the rules chain for each source/dest combination. # @dest_zones is the list of destination zones that we need to handle from this source zone # for my $zone1 ( @dest_zones ) { my $zone1ref = find_zone( $zone1 ); next if $filter_table->{rules_chain( ${zone}, ${zone1} )}->{policy} eq 'NONE'; my $chain = rules_target $zone, $zone1; next unless $chain; # CONTINUE policy with no rules my $num_ifaces = 0; if ( $zone eq $zone1 ) { next if ( $num_ifaces = scalar( keys ( %{$zoneref->{interfaces}} ) ) ) < 2 && ! $zoneref->{options}{in_out}{routeback}; } if ( $zone1ref->{type} == BPORT ) { next unless $zoneref->{bridge} eq $zone1ref->{bridge}; } my $chainref = $filter_table->{$chain}; #Will be null if $chain is a Netfilter Built-in target like ACCEPT if ( $frwd_ref ) { # # Simple case -- the source zone has it's own forwarding chain # for my $typeref ( values %{$zone1ref->{hosts}} ) { for my $interface ( sort { interface_number( $a ) <=> interface_number( $b ) } keys %$typeref ) { for my $hostref ( @{$typeref->{$interface}} ) { next if $hostref->{options}{sourceonly}; if ( $zone ne $zone1 || $num_ifaces > 1 || $hostref->{options}{routeback} ) { my @ipsec_out_match = match_ipsec_out $zone1 , $hostref; my $dest_exclusion = dest_exclusion( $hostref->{exclusions}, $chain); for my $net ( @{$hostref->{hosts}} ) { add_ijump $frwd_ref, j => $dest_exclusion, imatch_dest_dev( $interface) , imatch_dest_net($net), @ipsec_out_match; } } } } } } else { # # More compilcated case. If the interface is associated with a single simple zone, we try to combine the interface's forwarding chain with the rules chain # for my $typeref ( values %$source_hosts_ref ) { for my $interface ( keys %$typeref ) { my $interfaceref = find_interface $interface; my $chain3ref; my @match_source_dev; my $forwardchainref = $filter_table->{forward_chain $interface}; if ( use_forward_chain( $interface , $forwardchainref ) || ( @{$forwardchainref->{rules} } && ! $chainref ) ) { # # Either we must use the interface's forwarding chain or that chain has rules and we have nowhere to move them # $chain3ref = $forwardchainref; if ( $interfaceref->{options}{port} ) { add_ijump( $filter_table->{ forward_chain $interfaceref->{bridge} } , j => $chain3ref, imatch_source_dev( $interface , 1 ) ) unless $forward_jump_added{$interface}++; } else { add_ijump $filter_table->{FORWARD} , j => $chain3ref, imatch_source_dev( $interface ) unless $forward_jump_added{$interface}++; } } else { # # Don't use the interface's forward chain -- move any rules in that chain to this rules chain # if ( $interfaceref->{options}{port} ) { $chain3ref = $filter_table->{ forward_chain $interfaceref->{bridge} }; @match_source_dev = imatch_source_dev $interface, 1; } else { $chain3ref = $filter_table->{FORWARD}; @match_source_dev = imatch_source_dev $interface; } move_rules $forwardchainref, $chainref; } for my $hostref ( @{$typeref->{$interface}} ) { next if $hostref->{options}{destonly}; my $excl3ref = source_exclusion( $hostref->{exclusions}, $chain3ref ); for my $net ( @{$hostref->{hosts}} ) { for my $type1ref ( values %{$zone1ref->{hosts}} ) { for my $interface1 ( keys %$type1ref ) { my $array1ref = $type1ref->{$interface1}; for my $host1ref ( @$array1ref ) { next if $host1ref->{options}{sourceonly}; my @ipsec_out_match = match_ipsec_out $zone1 , $host1ref; my $dest_exclusion = dest_exclusion( $host1ref->{exclusions}, $chain ); for my $net1 ( @{$host1ref->{hosts}} ) { unless ( $interface eq $interface1 && $net eq $net1 && ! $host1ref->{options}{routeback} ) { # # We defer evaluation of the source net match to accomodate systems without $capabilities{KLUDEFREE}; # add_ijump( $excl3ref , j => $dest_exclusion, @match_source_dev, imatch_dest_dev($interface1), imatch_source_net($net), imatch_dest_net($net1), @ipsec_out_match ); } } } } } } } } } } } # # E N D F O R W A R D I N G # # Now add an unconditional jump to the last unique policy-only chain determined above, if any # add_ijump $frwd_ref , g => $last_chain if $frwd_ref && $last_chain; } progress_message ' Finishing matrix...'; add_interface_jumps @interfaces unless $interface_jumps_added; promote_blacklist_rules; my %builtins = ( mangle => [ qw/PREROUTING INPUT FORWARD POSTROUTING/ ] , nat=> [ qw/PREROUTING OUTPUT POSTROUTING/ ] , filter=> [ qw/INPUT FORWARD OUTPUT/ ] ); unless ( $config{COMPLETE} ) { complete_standard_chain $filter_table->{INPUT} , 'all' , firewall_zone , 'DROP'; complete_standard_chain $filter_table->{OUTPUT} , firewall_zone , 'all', 'REJECT'; complete_standard_chain $filter_table->{FORWARD} , 'all' , 'all', 'REJECT'; } if ( $config{LOGALLNEW} ) { for my $table ( qw/mangle nat filter/ ) { for my $chain ( @{$builtins{$table}} ) { log_rule_limit $config{LOGALLNEW} , $chain_table{$table}{$chain} , $table , $chain , '' , '' , 'insert' , "$globals{STATEMATCH} NEW "; } } } } sub setup_mss( ) { my $clampmss = $config{CLAMPMSS}; my $option; my @match; my $chainref = $filter_table->{FORWARD}; if ( $clampmss ) { if ( "\L$clampmss" eq 'yes' ) { $option = '--clamp-mss-to-pmtu'; } else { @match = ( tcpmss => "--mss $clampmss:" ) if have_capability( 'TCPMSS_MATCH' ); $option = "--set-mss $clampmss"; } push @match, ( policy => '--pol none --dir out' ) if have_ipsec; } my $interfaces = find_interfaces_by_option( 'mss' ); if ( @$interfaces ) { # # Since we will need multiple rules, we create a separate chain # $chainref = new_chain 'filter', 'settcpmss'; # # Send all forwarded SYN packets to the 'settcpmss' chain # add_ijump $filter_table->{FORWARD} , j => $chainref, p => 'tcp --tcp-flags SYN,RST SYN'; my @in_match = (); my @out_match = (); if ( have_ipsec ) { @in_match = ( policy => '--pol none --dir in' ); @out_match = ( policy => '--pol none --dir out' ); } for ( @$interfaces ) { my $mss = get_interface_option( $_, 'mss' ); my @mssmatch = have_capability( 'TCPMSS_MATCH' ) ? ( tcpmss => "--mss $mss:" ) : (); my @source = imatch_source_dev $_; my @dest = imatch_dest_dev $_; add_ijump $chainref, j => 'TCPMSS', targetopts => "--set-mss $mss", @dest, p => 'tcp --tcp-flags SYN,RST SYN', @mssmatch, @out_match; add_ijump $chainref, j => 'RETURN', @dest if $clampmss; add_ijump $chainref, j => 'TCPMSS', targetopts => "--set-mss $mss", @source, p => 'tcp --tcp-flags SYN,RST SYN', @mssmatch, @in_match; add_ijump $chainref, j => 'RETURN', @source if $clampmss; } } add_ijump $chainref , j => 'TCPMSS', targetopts => $option, p => 'tcp --tcp-flags SYN,RST SYN', @match if $clampmss; } # # Compile the stop_firewall() function # sub compile_stop_firewall( $$ ) { my ( $test, $export ) = @_; my $input = $filter_table->{INPUT}; my $output = $filter_table->{OUTPUT}; my $forward = $filter_table->{FORWARD}; emit <<'EOF'; # # Stop/restore the firewall after an error or because of a 'stop' or 'clear' command # stop_firewall() { local hack EOF $output->{policy} = 'ACCEPT' if $config{ADMINISABSENTMINDED}; if ( $family == F_IPV4 ) { emit <<'EOF'; deletechain() { qt $IPTABLES -L $1 -n && qt $IPTABLES -F $1 && qt $IPTABLES -X $1 } case $COMMAND in stop|clear|restore) if chain_exists dynamic; then ${IPTABLES}-save -t filter | grep '^-A dynamic' > ${VARDIR}/.dynamic fi ;; *) set +x EOF } else { emit <<'EOF'; deletechain() { qt $IPTABLES -L $1 -n && qt $IPTABLES -F $1 && qt $IPTABLES -X $1 } case $COMMAND in stop|clear|restore) if chain_exists dynamic; then ${IP6TABLES}-save -t filter | grep '^-A dynamic' > ${VARDIR}/.dynamic fi ;; *) set +x EOF } emit <<'EOF'; case $COMMAND in start) logger -p kern.err "ERROR:$g_product start failed" ;; restart) logger -p kern.err "ERROR:$g_product restart failed" ;; refresh) logger -p kern.err "ERROR:$g_product refresh failed" ;; enable) logger -p kern.err "ERROR:$g_product 'enable $g_interface' failed" ;; esac if [ "$RESTOREFILE" = NONE ]; then COMMAND=clear clear_firewall echo "$g_product Cleared" kill $$ exit 2 else g_restorepath=${VARDIR}/$RESTOREFILE if [ -x $g_restorepath ]; then echo Restoring ${g_product:=Shorewall}... g_recovering=Yes if run_it $g_restorepath restore; then echo "$g_product restored from $g_restorepath" set_state "Restored from $g_restorepath" else set_state "Unknown" fi kill $$ exit 2 fi fi ;; esac if [ -n "$g_stopping" ]; then kill $$ exit 1 fi set_state "Stopping" g_stopping="Yes" deletechain shorewall run_stop_exit EOF if ( have_capability( 'NAT_ENABLED' ) ) { emit<<'EOF'; if [ -f ${VARDIR}/nat ]; then while read external interface; do del_ip_addr $external $interface done < ${VARDIR}/nat rm -f ${VARDIR}/nat fi EOF } if ( $family == F_IPV4 ) { emit <<'EOF'; if [ -f ${VARDIR}/proxyarp ]; then while read address interface external haveroute; do qtnoin $IP -4 neigh del proxy $address dev $external [ -z "${haveroute}${g_noroutes}" ] && qtnoin $IP -4 route del $address/32 dev $interface f=/proc/sys/net/ipv4/conf/$interface/proxy_arp [ -f $f ] && echo 0 > $f done < ${VARDIR}/proxyarp rm -f ${VARDIR}/proxyarp fi EOF } else { emit <<'EOF'; if [ -f ${VARDIR}/proxyndp ]; then while read address interface external haveroute; do qtnoin $IP -6 neigh del proxy $address dev $external [ -z "${haveroute}${g_noroutes}" ] && qtnoin $IP -6 route del $address/128 dev $interface f=/proc/sys/net/ipv4/conf/$interface/proxy_ndp [ -f $f ] && echo 0 > $f done < ${VARDIR}/proxyndp rm -f ${VARDIR}/proxyndp fi EOF } push_indent; emit 'delete_tc1' if $config{CLEAR_TC}; emit( 'undo_routing', "restore_default_route $config{USE_DEFAULT_RT}" ); my @chains = $config{ADMINISABSENTMINDED} ? qw/INPUT FORWARD/ : qw/INPUT OUTPUT FORWARD/; add_ijump $filter_table ->{$_}, j => 'ACCEPT', state_imatch 'ESTABLISHED,RELATED' for @chains; if ( $family == F_IPV6 ) { add_ijump $input, j => 'ACCEPT', s => IPv6_LINKLOCAL; add_ijump $input, j => 'ACCEPT', d => IPv6_LINKLOCAL; add_ijump $input, j => 'ACCEPT', d => IPv6_MULTICAST; unless ( $config{ADMINISABSENTMINDED} ) { add_ijump $output, j => 'ACCEPT', d => IPv6_LINKLOCAL; add_ijump $output, j => 'ACCEPT', d => IPv6_MULTICAST; } } process_routestopped; add_ijump $input, j => 'ACCEPT', i => 'lo'; add_ijump $output, j => 'ACCEPT', o => 'lo' unless $config{ADMINISABSENTMINDED}; my $interfaces = find_interfaces_by_option 'dhcp'; if ( @$interfaces ) { my $ports = $family == F_IPV4 ? '67:68' : '546:547'; for my $interface ( @$interfaces ) { add_ijump $input, j => 'ACCEPT', p => "udp --dport $ports", imatch_source_dev( $interface ); add_ijump $output, j => 'ACCEPT', p => "udp --dport $ports", imatch_dest_dev( $interface ) unless $config{ADMINISABSENTMINDED}; # # This might be a bridge # add_ijump $forward, j => 'ACCEPT', p => "udp --dport $ports", imatch_source_dev( $interface ), imatch_dest_dev( $interface ); } } emit ''; create_stop_load $test; if ( $family == F_IPV4 ) { if ( $config{IP_FORWARDING} eq 'on' ) { emit( 'echo 1 > /proc/sys/net/ipv4/ip_forward', 'progress_message2 IPv4 Forwarding Enabled' ); } elsif ( $config{IP_FORWARDING} eq 'off' ) { emit( 'echo 0 > /proc/sys/net/ipv4/ip_forward', 'progress_message2 IPv4 Forwarding Disabled!' ); } } else { for my $interface ( all_bridges ) { emit "do_iptables -A FORWARD -p 58 " . match_source_dev( $interface ) . match_dest_dev( $interface ) . "-j ACCEPT"; } if ( $config{IP_FORWARDING} eq 'on' ) { emit( 'echo 1 > /proc/sys/net/ipv6/conf/all/forwarding', 'progress_message2 IPv6 Forwarding Enabled' ); } elsif ( $config{IP_FORWARDING} eq 'off' ) { emit( 'echo 0 > /proc/sys/net/ipv6/conf/all/forwarding', 'progress_message2 IPv6 Forwarding Disabled!' ); } } pop_indent; emit ' run_stopped_exit'; my @ipsets = all_ipsets; if ( @ipsets || ( $config{SAVE_IPSETS} && have_ipset_rules ) ) { emit <<'EOF'; case $IPSET in */*) if [ ! -x "$IPSET" ]; then error_message "ERROR: IPSET=$IPSET does not exist or is not executable - ipsets are not saved" IPSET= fi ;; *) IPSET="$(mywhich $IPSET)" [ -n "$IPSET" ] || error_message "ERROR: The ipset utility cannot be located - ipsets are not saved" ;; esac if [ -n "$IPSET" ]; then if [ -f /etc/debian_version ] && [ $(cat /etc/debian_version) = 5.0.3 ]; then # # The 'grep -v' is a hack for a bug in ipset's nethash implementation when xtables-addons is applied to Lenny # hack='| grep -v /31' else hack= fi if eval $IPSET -S $hack > ${VARDIR}/ipsets.tmp; then # # Don't save an 'empty' file # grep -qE '^(-N|create )' ${VARDIR}/ipsets.tmp && mv -f ${VARDIR}/ipsets.tmp ${VARDIR}/ipsets.save fi fi EOF } emit ' set_state "Stopped" logger -p kern.info "$g_product Stopped" case $COMMAND in stop|clear) ;; *) # # The firewall is being stopped when we were trying to do something # else. Kill the shell in case we\'re running in a subshell # kill $$ ;; esac } '; } 1;