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#!/usr/bin/perl
use lib "/opt/vyatta/share/perl5";
use warnings;
use strict;
use Vyatta::Config;
use Vyatta::Conntrack::RuleCT;
use Vyatta::IpTables::AddressFilter;
use Vyatta::Conntrack::ConntrackUtil;
use Getopt::Long;
use Vyatta::Zone;
use Sys::Syslog qw(:standard :macros);
#for future use when v6 timeouts need to be set
my %cmd_hash = ( 'ipv4' => 'iptables',
'ipv6' => 'ip6tables');
# Enable printing debug output to stdout.
my $debug_flag = 0;
# Enable sending debug output to syslog.
my $syslog_flag = 0;
my $nfct = "sudo /usr/sbin/nfct";
my ($create, $delete, $update);
my $CTERROR = "Conntrack timeout error:";
GetOptions("create=s" => \$create,
"delete=s" => \$delete,
"update=s" => \$update,
);
update_config();
openlog("vyatta-conntrack", "pid", "local0");
sub remove_timeout_policy {
my ($rule_string, $timeout_policy) = @_;
my @tokens = split (' ', $timeout_policy);
# First remove the iptables rules before removing policy.
my $iptables_cmd1 = "iptables -D VYATTA_CT_TIMEOUT -t raw $rule_string -j CT --timeout $tokens[0]";
my $iptables_cmd2 = "iptables -D VYATTA_CT_TIMEOUT -t raw $rule_string -j RETURN";
my $nfct_timeout_cmd = "$nfct timeout delete $timeout_policy";
run_cmd($iptables_cmd2);
if ($? >> 8) {
print "$CTERROR failed to run $iptables_cmd2\n";
#dont exit, try to clean as much.
}
run_cmd($iptables_cmd1);
if ($? >> 8) {
print "$CTERROR failed to run $iptables_cmd1\n";
}
run_cmd($nfct_timeout_cmd);
if ($? >> 8) {
print "$CTERROR failed to run $nfct_timeout_cmd\n";
}
}
# nfct-timeout create policy1 tcp established 1200 close-wait 100 fin-wait 10
# iptables -I PREROUTING -t raw -s 1.1.1.1 -d 2.2.2.2 -j CT --timeout policy1
#
# we have a chain setup, i.e. VYATTA_CT_TIMEOUT chain. Insert rule with timeout policy
# in the chain followed by another rule with matching 5 tuple to allow return
# from the point CT target matched. CT is non terminating and we want to keep
# behavior consistent with firewall, NAT etc.
sub apply_timeout_policy {
my ($rule_string, $timeout_policy, $rule, $num_rules) = @_;
my $nfct_timeout_cmd = "$nfct timeout add $timeout_policy";
my @tokens = split (' ', $timeout_policy);
# insert at num_rules + 1 as there are so many rules already.
my $iptables_cmd1 = "iptables -I VYATTA_CT_TIMEOUT $num_rules -t raw $rule_string -j CT --timeout $tokens[0]";
$num_rules +=1;
my $iptables_cmd2 = "iptables -I VYATTA_CT_TIMEOUT $num_rules -t raw $rule_string -j RETURN";
run_cmd($nfct_timeout_cmd);
if ($? >> 8) {
print "$CTERROR failed to run $nfct_timeout_cmd\n";
exit 1;
}
run_cmd($iptables_cmd1);
if ($? >> 8) {
#cleanup the policy before exit.
run_cmd("nfct timeout delete policy_timeout_$rule");
print "$CTERROR failed to run $iptables_cmd1\n";
exit 1;
}
run_cmd($iptables_cmd2);
if ($? >> 8) {
run_cmd("nfct timeout delete policy_timeout_$rule");
run_cmd("iptables -D PREROUTING -t raw $rule_string -j CT --timeout $tokens[0]");
print "$CTERROR failed to run $iptables_cmd2\n";
exit 1;
}
}
sub handle_rule_creation {
my ($rule, $num_rules) = @_;
my $node = new Vyatta::Conntrack::RuleCT;
my ($rule_string, $timeout_policy);
do_protocol_check($rule);
$node->setup("system conntrack timeout custom rule $rule");
$rule_string = $node->rule();
$timeout_policy = $node->get_policy_command("add"); #nfct-timeout command string
apply_timeout_policy($rule_string, $timeout_policy, $rule, $num_rules);
}
# we mandate only one protocol configuration per rule
sub do_protocol_check {
my ($rule) = @_;
my $config = new Vyatta::Config;
my $protocol_nos = $config->listNodes("system conntrack timeout custom rule $rule protocol");
if (($protocol_nos > 1) or ($protocol_nos < 1)) {
Vyatta::Config::outputError(["Conntrack"], "Conntrack config error: please configure exactly one protocol in rule $rule");
exit 1;
}
}
sub handle_rule_modification {
my ($rule, $num_rules) = @_;
do_protocol_check($rule);
handle_rule_deletion($rule);
handle_rule_creation($rule, $num_rules);
}
sub handle_rule_deletion {
my ($rule) = @_;
my $node = new Vyatta::Conntrack::RuleCT;
my ($rule_string, $timeout_policy);
$node->setupOrig("system conntrack timeout custom rule $rule");
$rule_string = $node->rule();
$timeout_policy = $node->get_policy_command("delete"); #nfct-timeout command string
remove_timeout_policy($rule_string, $timeout_policy);
}
sub numerically { $a <=> $b; }
sub update_config {
my $config = new Vyatta::Config;
my %rules = (); #hash of timeout config rules
my $iptables_cmd = $cmd_hash{'ipv4'};
$config->setLevel("system conntrack timeout custom rule");
%rules = $config->listNodeStatus();
my $iptablesrule = 1;
foreach my $rule (sort numerically keys %rules) {
if ("$rules{$rule}" eq 'static') {
$iptablesrule+=2;
} elsif ("$rules{$rule}" eq 'added') {
handle_rule_creation($rule, $iptablesrule);
$iptablesrule+=2;
} elsif ("$rules{$rule}" eq 'changed') {
handle_rule_modification($rule, $iptablesrule);
$iptablesrule+=2;
} elsif ("$rules{$rule}" eq 'deleted') {
handle_rule_deletion($rule);
}
}
}
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