shorewall_code/Shorewall-perl/Shorewall/Providers.pm
2008-12-08 21:49:50 +00:00

659 lines
20 KiB
Perl

#
# Shorewall-perl 4.2 -- /usr/share/shorewall-perl/Shorewall/Providers.pm
#
# This program is under GPL [http://www.gnu.org/licenses/old-licenses/gpl-2.0.txt]
#
# (c) 2007,2008 - 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 deals with the /etc/shorewall/providers and
# /etc/shorewall/route_rules files.
#
package Shorewall::Providers;
require Exporter;
use Shorewall::Config qw(:DEFAULT :internal);
use Shorewall::IPAddrs;
use Shorewall::Zones;
use Shorewall::Chains qw(:DEFAULT :internal);
use strict;
our @ISA = qw(Exporter);
our @EXPORT = qw( setup_providers @routemarked_interfaces);
our @EXPORT_OK = qw( initialize lookup_provider );
our $VERSION = 4.1.5;
use constant { LOCAL_TABLE => 255,
MAIN_TABLE => 254,
DEFAULT_TABLE => 253,
UNSPEC_TABLE => 0
};
our @routemarked_providers;
our %routemarked_interfaces;
our @routemarked_interfaces;
our $balance;
our $first_default_route;
our %providers;
our @providers;
#
# Initialize globals -- we take this novel approach to globals initialization to allow
# the compiler to run multiple times in the same process. The
# initialize() function does globals initialization for this
# module and is called from an INIT block below. The function is
# also called by Shorewall::Compiler::compiler at the beginning of
# the second and subsequent calls to that function.
#
sub initialize() {
@routemarked_providers = ();
%routemarked_interfaces = ();
@routemarked_interfaces = ();
$balance = 0;
$first_default_route = 1;
%providers = ( local => { number => LOCAL_TABLE , mark => 0 , optional => 0 } ,
main => { number => MAIN_TABLE , mark => 0 , optional => 0 } ,
default => { number => DEFAULT_TABLE , mark => 0 , optional => 0 } ,
unspec => { number => UNSPEC_TABLE , mark => 0 , optional => 0 } );
@providers = ();
}
INIT {
initialize;
}
#
# Set up marking for 'tracked' interfaces.
#
sub setup_route_marking() {
my $mask = $config{HIGH_ROUTE_MARKS} ? '0xFF00' : '0xFF';
require_capability( 'CONNMARK_MATCH' , 'the provider \'track\' option' , 's' );
require_capability( 'CONNMARK' , 'the provider \'track\' option' , 's' );
add_rule $mangle_table->{PREROUTING} , "-m connmark ! --mark 0/$mask -j CONNMARK --restore-mark --mask $mask";
add_rule $mangle_table->{OUTPUT} , "-m connmark ! --mark 0/$mask -j CONNMARK --restore-mark --mask $mask";
my $chainref = new_chain 'mangle', 'routemark';
my %marked_interfaces;
for my $providerref ( @routemarked_providers ) {
my $interface = $providerref->{interface};
my $base = uc chain_base $interface;
add_command( $chainref, qq(if [ -n "\$${base}_IS_UP" ]; then) ), incr_cmd_level( $chainref ) if $providerref->{optional};
unless ( $marked_interfaces{$interface} ) {
add_rule $mangle_table->{PREROUTING} , "-i $interface -m mark --mark 0/$mask -j routemark";
$marked_interfaces{$interface} = 1;
}
if ( $providerref->{shared} ) {
add_rule $chainref, " -i $interface -m mac --mac-source $providerref->{mac} -j MARK --set-mark $providerref->{mark}";
} else {
add_rule $chainref, " -i $interface -j MARK --set-mark $providerref->{mark}";
}
decr_cmd_level( $chainref), add_command( $chainref, "fi" ) if $providerref->{optional};
}
add_rule $chainref, "-m mark ! --mark 0/$mask -j CONNMARK --save-mark --mask $mask";
}
sub copy_table( $$$ ) {
my ( $duplicate, $number, $realm ) = @_;
if ( $realm ) {
emit ( "ip route show table $duplicate | sed -r 's/ realm [[:alnum:]_]+//' | while read net route; do" )
} else {
emit ( "ip route show table $duplicate | while read net route; do" )
}
emit ( ' case $net in',
' default|nexthop)',
' ;;',
' *)',
" run_ip route add table $number \$net \$route $realm",
' ;;',
' esac',
"done\n"
);
}
sub copy_and_edit_table( $$$$ ) {
my ( $duplicate, $number, $copy, $realm) = @_;
if ( $realm ) {
emit ( "ip route show table $duplicate | sed -r 's/ realm [[:alnum:]_]+//' | while read net route; do" )
} else {
emit ( "ip route show table $duplicate | while read net route; do" )
}
emit ( ' case $net in',
' default|nexthop)',
' ;;',
' *)',
' case $(find_device $route) in',
" $copy)",
" run_ip route add table $number \$net \$route $realm",
' ;;',
' esac',
' ;;',
' esac',
"done\n" );
}
sub balance_default_route( $$$$ ) {
my ( $weight, $gateway, $interface, $realm ) = @_;
$balance = 1;
emit '';
if ( $first_default_route ) {
if ( $gateway ) {
emit "DEFAULT_ROUTE=\"nexthop via $gateway dev $interface weight $weight $realm\"";
} else {
emit "DEFAULT_ROUTE=\"nexthop dev $interface weight $weight $realm\"";
}
$first_default_route = 0;
} else {
if ( $gateway ) {
emit "DEFAULT_ROUTE=\"\$DEFAULT_ROUTE nexthop via $gateway dev $interface weight $weight $realm\"";
} else {
emit "DEFAULT_ROUTE=\"\$DEFAULT_ROUTE nexthop dev $interface weight $weight $realm\"";
}
}
}
sub add_a_provider( $$$$$$$$ ) {
my ($table, $number, $mark, $duplicate, $interface, $gateway, $options, $copy) = @_;
fatal_error "Duplicate provider ($table)" if $providers{$table};
my $num = numeric_value $number;
fatal_error "Invalid Provider number ($number)" unless defined $num;
$number = $num;
for my $providerref ( values %providers ) {
fatal_error "Duplicate provider number ($number)" if $providerref->{number} == $number;
}
( $interface, my $address ) = split /:/, $interface;
my $shared = 0;
if ( defined $address ) {
validate_address $address, 0;
$shared = 1;
require_capability 'REALM_MATCH', "Configuring multiple providers through one interface", "s";
}
fatal_error "Unknown Interface ($interface)" unless known_interface $interface;
my $provider = chain_base $table;
my $base = uc chain_base $interface;
emit "#\n# Add Provider $table ($number)\n#";
emit "if interface_is_usable $interface; then";
push_indent;
emit "qt ip route flush table $number";
emit "echo \"qt ip route flush table $number\" >> \${VARDIR}/undo_routing";
if ( $gateway eq 'detect' ) {
fatal_error "'detect' is not allowed with USE_DEFAULT_RT=Yes" if $config{USE_DEFAULT_RT};
fatal_error "Configuring multiple providers through one interface requires an explicit gateway" if $shared;
$gateway = get_interface_gateway $interface;
} elsif ( $gateway && $gateway ne '-' ) {
validate_address $gateway, 0;
} else {
fatal_error "Configuring multiple providers through one interface requires a gateway" if $shared;
$gateway = '';
emit "run_ip route add default dev $interface table $number";
}
my $val = 0;
if ( $mark ne '-' ) {
$val = numeric_value $mark;
fatal_error "Invalid Mark Value ($mark)" unless defined $val;
verify_mark $mark;
if ( $val < 256) {
fatal_error "Invalid Mark Value ($mark) with HIGH_ROUTE_MARKS=Yes" if $config{HIGH_ROUTE_MARKS};
} else {
fatal_error "Invalid Mark Value ($mark) with HIGH_ROUTE_MARKS=No" if ! $config{HIGH_ROUTE_MARKS};
}
for my $providerref ( values %providers ) {
fatal_error "Duplicate mark value ($mark)" if $providerref->{mark} == $val;
}
my $pref = 10000 + $number - 1;
emit ( "qt ip rule del fwmark $mark" ) if $config{DELETE_THEN_ADD};
emit ( "run_ip rule add fwmark $mark pref $pref table $number",
"echo \"qt ip rule del fwmark $mark\" >> \${VARDIR}/undo_routing"
);
}
my ( $loose, $track, $balance , $default_balance, $optional, $mtu ) = (0,0,0,$config{USE_DEFAULT_RT} ? 1 : 0,interface_is_optional( $interface ), '' );
unless ( $options eq '-' ) {
for my $option ( split_list $options, 'option' ) {
if ( $option eq 'track' ) {
$track = 1;
} elsif ( $option =~ /^balance=(\d+)$/ ) {
$balance = $1;
} elsif ( $option eq 'balance' ) {
$balance = 1;
} elsif ( $option eq 'loose' ) {
$loose = 1;
$default_balance = 0;
} elsif ( $option eq 'optional' ) {
set_interface_option $interface, 'optional', 1;
$optional = 1;
} elsif ( $option =~ /^src=(.*)$/ ) {
fatal_error "OPTION 'src' not allowed on shared interface" if $shared;
$address = validate_address( $1 , 1 );
} elsif ( $option =~ /^mtu=(\d+)$/ ) {
$mtu = "mtu $1 ";
} else {
fatal_error "Invalid option ($option)";
}
}
}
$balance = $default_balance unless $balance;
$providers{$table} = { provider => $table,
number => $number ,
mark => $val ,
interface => $interface ,
optional => $optional ,
gateway => $gateway ,
shared => $shared };
if ( $track ) {
fatal_error "The 'track' option requires a numeric value in the MARK column" if $mark eq '-';
if ( $routemarked_interfaces{$interface} ) {
fatal_error "Interface $interface is tracked through an earlier provider" if $routemarked_interfaces{$interface} > 1;
fatal_error "Multiple providers through the same interface must their IP address specified in the INTERFACES" unless $shared;
} else {
$routemarked_interfaces{$interface} = $shared ? 1 : 2;
push @routemarked_interfaces, $interface;
}
push @routemarked_providers, $providers{$table};
}
my $realm = '';
if ( $shared ) {
$providers{$table}{mac} = get_interface_mac( $gateway, $interface , $table );
$realm = "realm $number";
}
if ( $duplicate ne '-' ) {
fatal_error "The DUPLICATE column must be empty when USE_DEFAULT_RT=Yes" if $config{USE_DEFAULT_RT};
if ( $copy eq '-' ) {
copy_table ( $duplicate, $number, $realm );
} else {
if ( $copy eq 'none' ) {
$copy = $interface;
} else {
$copy =~ tr/,/|/;
$copy = "$interface|$copy";
}
copy_and_edit_table( $duplicate, $number ,$copy , $realm);
}
} elsif ( $copy ne '-' ) {
fatal_error "The COPY column must be empty when USE_DEFAULT_RT=Yes" if $config{USE_DEFAULT_RT};
fatal_error 'A non-empty COPY column requires that a routing table be specified in the DUPLICATE column';
}
if ( $gateway ) {
$address = get_interface_address $interface unless $address;
emit "run_ip route replace $gateway src $address dev $interface ${mtu}table $number $realm";
emit "run_ip route add default via $gateway src $address dev $interface ${mtu}table $number $realm";
}
balance_default_route $balance , $gateway, $interface, $realm if $balance;
if ( $loose ) {
if ( $config{DELETE_THEN_ADD} ) {
emit ( "\nfind_interface_addresses $interface | while read address; do",
' qt ip rule del from $address',
'done'
);
}
} elsif ( $shared ) {
emit "qt ip rule del from $address" if $config{DELETE_THEN_ADD};
emit( "run_ip rule add from $address pref 20000 table $number" ,
"echo \"qt ip rule del from $address\" >> \${VARDIR}/undo_routing" );
} else {
my $rulebase = 20000 + ( 256 * ( $number - 1 ) );
emit "\nrulenum=0\n";
emit ( "find_interface_addresses $interface | while read address; do" );
emit ( ' qt ip rule del from $address' ) if $config{DELETE_THEN_ADD};
emit ( " run_ip rule add from \$address pref \$(( $rulebase + \$rulenum )) table $number",
" echo \"qt ip rule del from \$address\" >> \${VARDIR}/undo_routing",
' rulenum=$(($rulenum + 1))',
'done'
);
}
emit qq(\nprogress_message " Provider $table ($number) Added"\n);
emit ( "${base}_IS_UP=Yes" ) if $optional;
pop_indent;
emit 'else';
if ( $optional ) {
emit ( " error_message \"WARNING: Interface $interface is not configured -- Provider $table ($number) not Added\"",
" ${base}_IS_UP=" );
} else {
emit( " fatal_error \"Interface $interface is not configured -- Provider $table ($number) Cannot be Added\"" );
}
emit "fi\n";
}
sub add_an_rtrule( $$$$ ) {
my ( $source, $dest, $provider, $priority ) = @_;
unless ( $providers{$provider} ) {
my $found = 0;
if ( "\L$provider" =~ /^(0x[a-f0-9]+|0[0-7]*|[0-9]*)$/ ) {
my $provider_number = numeric_value $provider;
for ( keys %providers ) {
if ( $providers{$_}{number} == $provider_number ) {
$provider = $_;
$found = 1;
last;
}
}
}
fatal_error "Unknown provider ($provider)" unless $found;
}
fatal_error "You must specify either the source or destination in a route_rules entry" if $source eq '-' && $dest eq '-';
if ( $dest eq '-' ) {
$dest = 'to ' . ALLIP;
} else {
validate_net( $dest, 0 );
$dest = "to $dest";
}
if ( $source eq '-' ) {
$source = 'from ' . ALLIP;
} elsif ( $source =~ /:/ ) {
( my $interface, $source , my $remainder ) = split( /:/, $source, 3 );
fatal_error "Invalid SOURCE" if defined $remainder;
validate_net ( $source, 0 );
$source = "iif $interface from $source";
} elsif ( $source =~ /\..*\..*/ ) {
validate_net ( $source, 0 );
$source = "from $source";
} else {
$source = "iif $source";
}
fatal_error "Invalid priority ($priority)" unless $priority && $priority =~ /^\d{1,5}$/;
$priority = "priority $priority";
emit ( "qt ip rule del $source $dest $priority" ) if $config{DELETE_THEN_ADD};
my ( $optional, $number ) = ( $providers{$provider}{optional} , $providers{$provider}{number} );
if ( $optional ) {
my $base = uc chain_base( $providers{$provider}{interface} );
emit ( '', "if [ -n \$${base}_IS_UP ]; then" );
push_indent;
}
emit ( "run_ip rule add $source $dest $priority table $number",
"echo \"qt ip rule del $source $dest $priority\" >> \${VARDIR}/undo_routing" );
pop_indent, emit ( "fi\n" ) if $optional;
progress_message " Routing rule \"$currentline\" $done";
}
#
# This probably doesn't belong here but looking forward to the day when we get Shorewall out of the routing business,
# it makes sense to keep all of the routing code together
#
sub setup_null_routing() {
save_progress_message "Null Routing the RFC 1918 subnets";
for ( rfc1918_networks ) {
emit( "run_ip route replace unreachable $_" );
emit( "echo \"qt ip route del unreachable $_\" >> \${VARDIR}/undo_routing" );
}
}
sub setup_providers() {
my $providers = 0;
my $fn = open_file 'providers';
while ( read_a_line ) {
unless ( $providers ) {
progress_message2 "$doing $fn ...";
require_capability( 'MANGLE_ENABLED' , 'a non-empty providers file' , 's' );
fatal_error "A non-empty providers file is not permitted with MANGLE_ENABLED=No" unless $config{MANGLE_ENABLED};
emit "\nif [ -z \"\$NOROUTES\" ]; then";
push_indent;
emit ( '#',
'# Undo any changes made since the last time that we [re]started -- this will not restore the default route',
'#',
'undo_routing' );
unless ( $config{KEEP_RT_TABLES} ) {
emit (
'#',
'# Save current routing table database so that it can be restored later',
'#',
'cp /etc/iproute2/rt_tables ${VARDIR}/' );
}
emit ( '#',
'# Capture the default route(s) if we don\'t have it (them) already.',
'#',
'[ -f ${VARDIR}/default_route ] || ip route list | grep -E \'^\s*(default |nexthop )\' > ${VARDIR}/default_route',
'#',
'# Initialize the file that holds \'undo\' commands',
'#',
'> ${VARDIR}/undo_routing' );
save_progress_message 'Adding Providers...';
emit 'DEFAULT_ROUTE=';
}
my ( $table, $number, $mark, $duplicate, $interface, $gateway, $options, $copy ) = split_line 6, 8, 'providers file';
add_a_provider( $table, $number, $mark, $duplicate, $interface, $gateway, $options, $copy );
push @providers, $table;
$providers++;
progress_message " Provider \"$currentline\" $done";
}
if ( $providers ) {
if ( $balance ) {
my $table = MAIN_TABLE;
if ( $config{USE_DEFAULT_RT} ) {
emit ( 'run_ip rule add from all table ' . MAIN_TABLE . ' pref 999',
'ip rule del from all table ' . MAIN_TABLE . ' pref 32766',
'echo "qt ip rule add from all table ' . MAIN_TABLE . ' pref 32766" >> ${VARDIR}/undo_routing',
'echo "qt ip rule del from all table ' . MAIN_TABLE . ' pref 999" >> ${VARDIR}/undo_routing',
'' );
$table = DEFAULT_TABLE;
}
emit ( 'if [ -n "$DEFAULT_ROUTE" ]; then' );
emit ( " run_ip route replace default scope global table $table \$DEFAULT_ROUTE" );
emit ( ' qt ip route del default table ' . MAIN_TABLE ) if $config{USE_DEFAULT_RT};
emit ( " progress_message \"Default route '\$(echo \$DEFAULT_ROUTE | sed 's/\$\\s*//')' Added\"",
'else',
' error_message "WARNING: No Default route added (all \'balance\' providers are down)"',
' restore_default_route',
'fi',
'' );
} else {
emit ( '#',
'# We don\'t have any \'balance\' providers so we restore any default route that we\'ve saved',
'#',
'restore_default_route' );
}
unless ( $config{KEEP_RT_TABLES} ) {
emit( 'if [ -w /etc/iproute2/rt_tables ]; then',
' cat > /etc/iproute2/rt_tables <<EOF' );
push_indent;
emit_unindented join( "\n",
'#',
'# reserved values',
'#',
LOCAL_TABLE . "\tlocal",
MAIN_TABLE . "\tmain",
DEFAULT_TABLE . "\tdefault",
"0\tunspec",
'#',
'# local',
'#',
"EOF\n" );
emit "echocommand=\$(find_echo)\n";
for my $table ( @providers ) {
emit "\$echocommand \"$providers{$table}{number}\\t$table\" >> /etc/iproute2/rt_tables";
}
pop_indent;
emit "fi\n";
}
my $fn = open_file 'route_rules';
if ( $fn ) {
first_entry "$doing $fn...";
emit '';
while ( read_a_line ) {
my ( $source, $dest, $provider, $priority ) = split_line 4, 4, 'route_rules file';
add_an_rtrule( $source, $dest, $provider , $priority );
}
}
setup_null_routing if $config{NULL_ROUTE_RFC1918};
emit "\nrun_ip route flush cache";
pop_indent;
emit "fi\n";
setup_route_marking if @routemarked_interfaces;
} else {
emit "\nundo_routing";
emit 'restore_default_route';
if ( $config{NULL_ROUTE_RFC1918} ) {
emit "\nif [ -z \"\$NOROUTES\" ]; then";
push_indent;
emit ( '#',
'# Initialize the file that holds \'undo\' commands',
'#',
'> ${VARDIR}/undo_routing' );
setup_null_routing;
emit "\nrun_ip route flush cache";
pop_indent;
emit "fi\n";
}
}
}
sub lookup_provider( $ ) {
my $provider = $_[0];
my $providerref = $providers{ $provider };
unless ( $providerref ) {
fatal_error "Unknown provider ($provider)" unless $provider =~ /^(0x[a-f0-9]+|0[0-7]*|[0-9]*)$/;
my $provider_number = numeric_value $provider;
for ( keys %providers ) {
if ( $providers{$_}{number} == $provider_number ) {
$providerref = $providers{$_};
last;
}
}
fatal_error "Unknown provider ($provider)" unless $providerref;
}
$providerref->{shared} ? $providerref->{number} : 0;
}
1;