shorewall_code/New/Shorewall/Rules.pm
2007-03-15 00:34:17 +00:00

631 lines
14 KiB
Perl

package Shorewall::Rules;
require Exporter;
use strict;
use Shorewall::Common;
use Shorewall::Config;
use Shorewall::Chains;
use Shorewall::Zones;
use Shorewall::Interfaces;
our @ISA = qw(Exporter);
our @EXPORT = qw( STANDARD
NATRULE
BUILTIN
NONAT
NATONLY
REDIRECT
ACTION
MACRO
LOGRULE
do_proto
mac_match
numeric_value
verify_mark
verify_small_mark
validate_mark
do_test
do_ratelimit
do_user
iprange_match
match_source_net
match_dest_net
match_orig_dest
match_ipsec_in
match_ipsec_out
log_rule_limit
log_rule
expand_rule
addnatjump
insertnatjump
%targets
);
our @EXPORT_OK = ();
our @VERSION = 1.00;
#
#
# Handle parsing of PROTO, DEST PORT(S) , SOURCE PORTS(S). Returns the appropriate match string.
#
sub do_proto( $$$ )
{
my ($proto, $ports, $sports ) = @_;
my $output = '';
$proto = '' unless defined $proto;
$ports = '' unless defined $ports;
$sports = '' unless defined $sports;
$proto = '' if $proto eq '-';
$ports = '' if $ports eq '-';
$sports = '' if $sports eq '-';
if ( $proto ) {
if ( $proto =~ /^(tcp|udp|6|17)$/i ) {
$output = "-p $proto ";
if ( $ports ) {
my @ports = split /,/, $ports;
my $count = @ports;
if ( $count > 1 ) {
fatal_error "Port list requires Multiport support in your kernel/iptables: $ports" unless $capabilities{MULTIPORT};
fatal_error "Port range in a list requires Extended Multiport Support in your kernel/iptables: $ports" unless $capabilities{XMULTIPORT};
for my $port ( @ports ) {
$count++ if $port =~ /:/;
}
fatal_error "Too many entries in port list: $ports" if $count > 15;
$output .= "-m multiport --dports $ports ";
} else {
$output .= "--dport $ports ";
}
}
if ( $sports ) {
my @ports = split /,/, $sports;
my $count = @ports;
if ( $count > 1 ) {
fatal_error "Port list requires Multiport support in your kernel/iptables: $sports" unless $capabilities{MULTIPORT};
fatal_error "Port range in a list requires Extended Multiport Support in your kernel/iptables: $sports" unless $capabilities{XMULTIPORT};
for my $port ( @ports ) {
$count++ if $port =~ /:/;
}
fatal_error "Too many entries in port list: $sports" if $count > 15;
$output .= "-m multiport --sports $sports ";
} else {
$output .= "--sport $sports ";
}
}
} elsif ( $proto =~ /^(icmp|1)$/i ) {
$output .= "-p icmp --icmp-type $ports " if $ports;
fatal_error 'SOURCE PORT(S) not permitted with ICMP' if $sports;
} elsif ( $proto =~ /^(ipp2p(:(tcp|udp|all)))?$/i ) {
fatal_error 'PROTO = ipp2p requires IPP2P match support in your kernel/iptables' unless $capabilities{IPP2P};
$proto = $2 ? $3 : 'tcp';
$ports = 'ipp2p' unless $ports;
$output .= "-p $proto -m ipp2p --$ports ";
}
} elsif ( $ports || $sports ) {
fatal_error "SOURCE/DEST PORT(S) not allowed without PROTO, rule \"$line\""
}
$output;
}
sub mac_match( $ ) {
my $mac = $_[0];
$mac =~ s/^(!?)~//;
$mac =~ s/^!// if my $invert = $1 ? '! ' : '';
$mac =~ s/-/:/g;
"--match mac --mac-source ${invert}$mac ";
}
#
# Convert value to decimal number
#
sub numeric_value ( $ ) {
my $mark = $_[0];
$mark =~ /^0x/ ? hex $mark : $mark =~ /^0/ ? oct $mark : $mark;
}
#
# Mark validatation functions
#
sub verify_mark( $ ) {
my $mark = $_[0];
my $limit = $config{HIGH_ROUTE_MARKS} ? 0xFFFF : 0xFF;
fatal_error "Invalid Mark or Mask value: $mark"
unless "\L$mark" =~ /^(0x[a-f0-9]+|0[0-7]*|[0-9]*)$/ && numeric_value( $mark ) <= $limit;
}
sub verify_small_mark( $ ) {
verify_mark ( (my $mark) = $_[0] );
fatal_error "Mark value ($mark) too large" if numeric_value( $mark ) > 0xFF;
}
sub validate_mark( $ ) {
for ( split '/', $_[0] ) {
verify_mark $_;
}
}
#
# Generate an appropriate -m [conn]mark match string for the contents of a MARK column
#
sub do_test ( $$ )
{
my ($testval, $mask) = @_;
return '' unless $testval and $testval ne '-';
my $invert = $testval =~ s/^!// ? '! ' : '';
my $match = $testval =~ s/:C$// ? '-m connmark ' : '-m mark ';
$testval .= '/0xFF' unless ( $testval =~ '/' );
"${invert}$match $testval ";
}
#
# Create a "-m limit" match for the passed LIMIT/BURST
#
sub do_ratelimit( $ ) {
my $rate = $_[0];
return '' unless $rate and $rate ne '-';
if ( $rate =~ /^([^:]+):([^:]+)$/ ) {
"-m limit --limit $1 --limit-burst $2 ";
} else {
"-m limit --limit $rate ";
}
}
#
# Create a "-m owner" match for the passed USER/GROUP
#
sub do_user( $ ) {
my $user = $_[0];
my $rule = ' -m owner';
return '' unless $user and $user ne '-';
if ( $user =~ /^(!)?(.*)\+(.*)$/ ) {
$rule .= "! --cmd-owner $2 " if $2;
$user = "!$1";
} elsif ( $user =~ /^(.*)\+(.*)$/ ) {
$rule .= "--cmd-owner $2 " if $2;
$user = $1;
}
if ( $user =~ /^!(.*):(.*)$/ ) {
$rule .= "! --uid-owner $1 " if $1;
$rule .= "! --gid-owner $2 " if $2;
} elsif ( $user =~ /^(.*):(.*)$/ ) {
$rule .= "--uid-owner $1 " if $1;
$rule .= "--gid-owner $2 " if $2;
} elsif ( $user =~ /^!/ ) {
$rule .= "! --uid-owner $user ";
} else {
$rule .= "--uid-owner $user ";
}
$rule;
}
#
# Avoid generating a second '-m iprange' in a single rule.
#
sub iprange_match() {
my $match = '';
unless ( $iprangematch ) {
$match = '-m iprange ';
$iprangematch = 1;
}
$match;
}
#
# Match a Source. Currently only handles IP addresses and ranges
#
sub match_source_net( $ ) {
my $net = $_[0];
if ( $net =~ /^(!?).*\..*\..*\..*-.*\..*\..*\..*/ ) {
$net =~ s/!// if my $invert = $1 ? '! ' : '';
iprange_match . "${invert}--src-range $net ";
} elsif ( $net =~ /^(!?)~(.*)$/ ) {
( $net = $2 ) =~ s/-/:/g;
"-m mac --mac-source $1 $net "
} elsif ( $net =~ /^!/ ) {
$net =~ s/!//;
"-s ! $net ";
} else {
$net eq ALLIPv4 ? '' : "-s $net ";
}
}
#
# Match a Source. Currently only handles IP addresses and ranges
#
sub match_dest_net( $ ) {
my $net = $_[0];
if ( $net =~ /^(!?).*\..*\..*\..*-.*\..*\..*\..*/ ) {
$net =~ s/!// if my $invert = $1 ? '! ' : '';
iprange_match . "${invert}--src-range $net ";
} elsif ( $net =~ /^!/ ) {
$net =~ s/!//;
"-d ! $net ";
} else {
$net eq ALLIPv4 ? '' : "-d $net ";
}
}
#
# Match original destination
#
sub match_orig_dest ( $ ) {
my $net = $_[0];
return '' if $net eq ALLIPv4;
if ( $net =~ /^!/ ) {
$net =~ s/!//;
"-m conntrack --ctorigdst ! $net ";
} else {
$net eq ALLIPv4 ? '' : "-m conntrack --ctorigdst $net ";
}
}
#
# Match Source IPSEC
#
sub match_ipsec_in( $$ ) {
my ( $zone , $hostref ) = @_;
my $match = '-m policy --dir in --pol ';
my $zoneref = $zones{$zone};
my $optionsref = $zoneref->{options};
if ( $zoneref->{type} eq 'ipsec4' ) {
$match .= "ipsec $optionsref->{in_out}{ipsec}$optionsref->{in}{ipsec}";
} elsif ( $capabilities{POLICY_MATCH} ) {
$match .= "$hostref->{ipsec} $optionsref->{in_out}{ipsec}$optionsref->{in}{ipsec}";
} else {
'';
}
}
#
# Match Dest IPSEC
#
sub match_ipsec_out( $$ ) {
my ( $zone , $hostref ) = @_;
my $match = '-m policy --dir out --pol ';
my $zoneref = $zones{$zone};
my $optionsref = $zoneref->{options};
if ( $zoneref->{type} eq 'ipsec4' ) {
$match .= "ipsec $optionsref->{in_out}{ipsec}$optionsref->{out}{ipsec}";
} elsif ( $capabilities{POLICY_MATCH} ) {
$match .= "$hostref->{ipsec} $optionsref->{in_out}{ipsec}$optionsref->{out}{ipsec}"
} else {
'';
}
}
#
# Generate a log message
#
sub log_rule_limit( $$$$$$$$ ) {
my ($level, $chainref, $chain, $disposition, $limit, $tag, $command, $predicates ) = @_;
my $prefix;
$limit = $env{LOGLIMIT} unless $limit;
if ( $tag ) {
if ( $config{LOGTAGONLY} ) {
$chain = $tag;
$tag = '';
} else {
$tag .= ' ';
}
} else {
$tag = '' unless defined $tag;
}
if ( $env{LOGRULENUMBERS} ) {
$prefix = (sprintf $config{LOGFORMAT} , $chain , $chainref->{log}++, $disposition ) . $tag;
} else {
$prefix = (sprintf $config{LOGFORMAT} , $chain , $disposition) . $tag;
}
if ( length $prefix > 29 ) {
$prefix = substr $prefix, 0, 29;
warning_message "Log Prefix shortened to \"$prefix\"";
}
if ( $level eq 'ULOG' ) {
$prefix = "-j ULOG $env{LOGPARMS} --ulog-prefix \"$prefix\" ";
} else {
$prefix = "-j LOG $env{LOGPARMS} --log-level $level --log-prefix \"$prefix\" ";
}
if ( $command eq 'add' ) {
add_rule ( $chainref, $predicates . $prefix );
} else {
insert_rule ( $chainref , 1 , $predicates . $prefix );
}
}
sub log_rule( $$$$ ) {
my ( $level, $chainref, $disposition, $predicates ) = @_;
log_rule_limit $level, $chainref, $chainref->{name} , $disposition, $env{LOGLIMIT}, '', 'add', $predicates;
}
#
# This function provides a uniform way to generate rules (something the original Shorewall sorely needed).
#
sub expand_rule( $$$$$$$$$ )
{
my ($chainref , $rule, $source, $dest, $origdest, $target, $loglevel , $disposition, $exceptionrule ) = @_;
my ($iiface, $diface, $inets, $dnets, $iexcl, $dexcl, $onets , $oexcl );
#
# Isolate Source Interface, if any
#
if ( $source ) {
if ( $source eq '-' ) {
$source = '';
} elsif ( $source =~ /^([^:]+):([^:]+)$/ ) {
$iiface = $1;
$inets = $2;
} elsif ( $source =~ /\+|~|\..*\./ ) {
$inets = $source;
} else {
$iiface = $source;
}
} else {
$source = '';
}
#
# Verify Inteface, if any
#
if ( $iiface ) {
fatal_error "Unknown Interface ($iiface): \"$line\"" unless known_interface $iiface;
$rule .= "-i $iiface ";
}
#
# Isolate Destination Interface, if any
#
if ( $dest ) {
if ( $dest eq '-' ) {
$dest = '';
} elsif ( $dest =~ /^([^:]+):([^:]+)$/ ) {
$diface = $1;
$dnets = $2;
} elsif ( $dest =~ /\+|~|\..*\./ ) {
$dnets = $dest;
} else {
$diface = $dest;
}
} else {
$dest = '';
}
#
# Verify Destination Interface, if any
#
if ( $diface ) {
fatal_error "Unknown Interface ($diface) in rule \"$line\"" unless known_interface $diface;
$rule .= "-o $diface ";
}
#
# Handle Log Level
#
my $logtag;
if ( $loglevel ) {
( $loglevel, $logtag ) = split /:/, $loglevel;
if ( $loglevel =~ /^none!?$/i ) {
return 1 if $disposition eq 'LOG';
$loglevel = $logtag = '';
}
}
#
# Determine if there is Source Exclusion
#
if ( $inets ) {
if ( $inets =~ /^([^!]+)?!([^!]+)$/ ) {
$inets = $1;
$iexcl = $2;
} else {
$iexcl = '';
}
if ( ! $inets ) {
my @iexcl = split /,/, $iexcl;
if ( @iexcl == 1 ) {
$rule .= match_source_net "!$iexcl ";
$iexcl = '';
}
}
} else {
$iexcl = '';
}
#
# Determine if there is Destination Exclusion
# $dexcl = '';
if ( $dnets ) {
if ( $dnets =~ /^([^!]+)?!([^!]+)$/ ) {
$dnets = $1;
$dexcl = $2;
} else {
$dexcl = '';
}
if ( ! $dnets ) {
my @dexcl = split /,/, $dexcl;
if ( @dexcl == 1 ) {
$rule .= match_dest_net "!$dexcl ";
$dexcl = '';
}
}
} else {
$dexcl = '';
}
if ( $origdest ) {
if ( $origdest =~ /^([^!]+)?!([^!]+)$/ ) {
$onets = $1;
$oexcl = $2;
} else {
$oexcl = '';
}
if ( ! $onets ) {
my @oexcl = split /,/, $oexcl;
if ( @oexcl == 1 ) {
$rule .= "-m conntrack --ctorigdst ! $oexcl ";
$oexcl = '';
}
}
} else {
$oexcl = '';
}
$inets = ALLIPv4 unless $inets;
$dnets = ALLIPv4 unless $dnets;
$onets = ALLIPv4 unless $onets;
if ( $iexcl || $dexcl || $oexcl ) {
#
# We have non-trivial exclusion -- need to create an exclusion chain
#
my $echain = newexclusionchain;
#
# Use the current rule and sent all possible matches to the exclusion chain
#
for my $onet ( split /,/, $onets ) {
$onet = match_orig_dest $onet;
for my $inet ( split /,/, $inets ) {
$inet = match_source_net $inet;
for my $dnet ( split /,/, $dnets ) {
add_rule $chainref, $rule . $inet . ( match_dest_net $dnet ) . $onet . "-j $echain";
}
}
}
#
# The final rule in the exclusion chain will not qualify the source or destination
#
$inets = ALLIPv4;
$dnets = ALLIPv4;
#
# Create the Exclusion Chain
#
my $echainref = new_chain $chainref->{table}, $echain;
#
# Generate RETURNs for each exclusion
#
for my $net ( split ',', $iexcl ) {
add_rule $echainref, ( match_source_net $net ) . '-j RETURN';
}
for my $net ( split ',', $dexcl ) {
add_rule $echainref, ( match_dest_net $net ) . '-j RETURN';
}
for my $net ( split ',', $oexcl ) {
add_rule $echainref, ( match_orig_dest $net ) . '-j RETURN';
}
#
# Log rule
#
log_rule_limit $loglevel , $echainref , $chainref->{name}, $disposition , '', $logtag , 'add' , '' if $loglevel;
#
# Generate Final Rule
#
add_rule $echainref, $exceptionrule . $target unless $disposition eq 'LOG';
} else {
#
# No exclusions
#
for my $onet ( split /,/, $onets ) {
$onet = match_orig_dest $onet;
for my $inet ( split /,/, $inets ) {
$inet = match_source_net $inet;
for my $dnet ( split /,/, $dnets ) {
log_rule_limit $loglevel , $chainref , $chainref->{name}, $disposition , '' , $logtag , 'add' , $rule . $inet . match_dest_net( $dnet ) . $onet if $loglevel;
add_rule $chainref, $rule . $inet . match_dest_net( $dnet ) . $onet . $target unless $disposition eq 'LOG';
}
}
}
}
}
#
# If the destination chain exists, then at the end of the source chain add a jump to the destination.
#
sub addnatjump( $$$ ) {
my ( $source , $dest, $predicates ) = @_;
my $destref = $nat_table->{$dest} || {};
if ( $destref->{referenced} ) {
add_rule $nat_table->{$source} , $predicates . "-j $dest";
} else {
clearrule;
}
}
#
# If the destination chain exists, then at the position in the source chain given by $$countref, add a jump to the destination.
#
sub insertnatjump( $$$$ ) {
my ( $source, $dest, $countref, $predicates ) = @_;
my $destref = $nat_table->{$dest} || {};
if ( $destref->{referenced} ) {
insert_rule $nat_table->{$source} , ($$countref)++, $predicates . "-j $dest";
} else {
clearrule;
}
}
1;