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|
#!/usr/bin/perl
use strict;
use lib "/opt/vyatta/share/perl5/";
use VyattaConfig;
use VyattaNatRule;
sub numerically { $a <=> $b; }
sub raw_cleanup {
# remove the conntrack setup.
my @lines
= `iptables -t raw -L PREROUTING -vn --line-numbers | egrep ^[0-9]`;
foreach (@lines) {
my ($num, $ignore, $ignore, $chain, $ignore, $ignore, $in, $out,
$ignore, $ignore) = split /\s+/;
if ($chain eq "NAT_CONNTRACK") {
system("iptables -t raw -D PREROUTING $num");
system("iptables -t raw -D OUTPUT $num");
system("iptables -t raw -F NAT_CONNTRACK");
system("iptables -t raw -X NAT_CONNTRACK");
last;
}
}
}
my $config = new VyattaConfig;
$config->setLevel("service nat rule");
my %rules = $config->listNodeStatus();
my $rule;
open(OUT, ">>/dev/null") or exit 1;
my %ipt_rulenum = (
source => 1,
destination => 1,
);
my %chain_name = (
source => "POSTROUTING",
destination => "PREROUTING",
);
print OUT "========= nat list =========\n";
my @rule_keys = sort numerically keys %rules;
if ($#rule_keys < 0) {
# no rules (everything is deleted) => flush the nat table & return
print OUT "iptables -t nat -F\n";
if (system("iptables -t nat -F")) {
exit 1;
}
raw_cleanup();
exit 0;
}
## it seems that "multiport" does not like port range (p1:p2) if nobody has
## touched the nat table yet after reboot!?
system("iptables -t nat -L -n >& /dev/null");
# we have some nat rule(s). make sure conntrack is enabled.
system("iptables -t raw -L NAT_CONNTRACK -n >& /dev/null");
if ($? >> 8) {
# NAT_CONNTRACK chain does not exist yet. set up conntrack.
system("iptables -t raw -N NAT_CONNTRACK");
# this enables conntrack for all packets. potentially we can add more rules
# to the NAT_CONNTRACK chain for finer-grained control over which packets
# are tracked.
system("iptables -t raw -A NAT_CONNTRACK -j ACCEPT");
system("iptables -t raw -I PREROUTING 1 -j NAT_CONNTRACK");
system("iptables -t raw -I OUTPUT 1 -j NAT_CONNTRACK");
}
my $all_deleted = 1;
for $rule (@rule_keys) {
print OUT "$rule: $rules{$rule}\n";
my $nrule = new VyattaNatRule;
$nrule->setup("service nat rule $rule");
my $otype = $nrule->orig_type();
my $ntype = $nrule->new_type();
if ((defined($otype) && $otype ne "source" && $otype ne "destination")
|| (defined($ntype) && $ntype ne "source" && $ntype ne "destination")) {
exit 2;
}
if ($rules{$rule} ne "deleted") {
$all_deleted = 0;
}
my $cmd;
if ($rules{$rule} eq "static") {
# $otype and $ntype should be the same
if (!defined($ntype)) {
exit 3;
}
$ipt_rulenum{$ntype} += 1;
next;
} elsif ($rules{$rule} eq "deleted") {
# $ntype should be empty
if (!defined($otype)) {
exit 4;
}
$cmd = "iptables -t nat -D $chain_name{$otype} $ipt_rulenum{$otype}";
print OUT "$cmd\n";
if (system($cmd)) {
exit 1;
}
next;
}
my ($str, $err) = $nrule->rule_str();
if (!defined($str)) {
# rule check failed => return error
print OUT "ERROR: $err\n";
print STDERR "ERROR: $err\n";
exit 5;
}
if ($rules{$rule} eq "added") {
# $otype should be empty
if (!defined($ntype)) {
exit 6;
}
$cmd = "iptables -t nat -I $chain_name{$ntype} $ipt_rulenum{$ntype} " .
"$str";
print OUT "$cmd\n";
if (system($cmd)) {
exit 1;
}
$ipt_rulenum{$ntype} += 1;
} elsif ($rules{$rule} eq "changed") {
# $otype and $ntype may not be the same
if (!defined($otype) || !defined($ntype)) {
exit 7;
}
$cmd = "iptables -t nat -I $chain_name{$ntype} $ipt_rulenum{$ntype} " .
"$str";
print OUT "$cmd\n";
if (system($cmd)) {
exit 1;
}
my $idx = $ipt_rulenum{$otype};
if ($otype eq $ntype) {
$idx += 1;
}
$cmd = "iptables -t nat -D $chain_name{$otype} $idx";
print OUT "$cmd\n";
if (system($cmd)) {
exit 1;
}
$ipt_rulenum{$ntype} += 1;
}
}
if ($all_deleted) {
raw_cleanup();
}
close OUT;
exit 0;
|
