package PVE::FirewallSimulator; use strict; use warnings; use Data::Dumper; use PVE::Firewall; use File::Basename; use Net::IP; my $mark; my $trace; my $debug = 0; sub debug { my $new_value = shift; $debug = $new_value if defined($new_value); return $debug; } sub reset_trace { $trace = ''; } sub get_trace { return $trace; } sub add_trace { my ($text) = @_; if ($debug) { print $text; } else { $trace .= $text; } } $SIG{'__WARN__'} = sub { my $err = $@; my $t = $_[0]; chomp $t; add_trace("$t\n"); $@ = $err; }; sub nf_dev_match { my ($devre, $dev) = @_; $devre =~ s/\+$/\.\*/; return ($dev =~ m/^${devre}$/) ? 1 : 0; } sub ipset_match { my ($ipsetname, $ipset, $ipaddr) = @_; my $ip = Net::IP->new($ipaddr); foreach my $entry (@$ipset) { next if $entry =~ m/^create/; # simply ignore if ($entry =~ m/add \S+ (\S+)$/) { my $test = Net::IP->new($1); if ($test->overlaps($ip)) { add_trace("IPSET $ipsetname match $ipaddr\n"); return 1; } } else { die "implement me"; } } return 0; } sub rule_match { my ($ipset_ruleset, $chain, $rule, $pkg) = @_; $rule =~ s/^-A $chain // || die "got strange rule: $rule"; while (length($rule)) { if ($rule =~ s/^-m conntrack --ctstate (\S+)\s*//) { my $cstate = $1; return undef if $cstate eq 'INVALID'; # no match return undef if $cstate eq 'RELATED,ESTABLISHED'; # no match next if $cstate =~ m/NEW/; die "cstate test '$cstate' not implemented\n"; } if ($rule =~ s/^-m addrtype --src-type (\S+)\s*//) { my $atype = $1; die "missing source address type (srctype)\n" if !$pkg->{srctype}; return undef if $atype ne $pkg->{srctype}; } if ($rule =~ s/^-m addrtype --dst-type (\S+)\s*//) { my $atype = $1; die "missing destination address type (dsttype)\n" if !$pkg->{dsttype}; return undef if $atype ne $pkg->{dsttype}; } if ($rule =~ s/^-i (\S+)\s*//) { my $devre = $1; die "missing interface (iface_in)\n" if !$pkg->{iface_in}; return undef if !nf_dev_match($devre, $pkg->{iface_in}); next; } if ($rule =~ s/^-o (\S+)\s*//) { my $devre = $1; die "missing interface (iface_out)\n" if !$pkg->{iface_out}; return undef if !nf_dev_match($devre, $pkg->{iface_out}); next; } if ($rule =~ s/^-p (tcp|udp|igmp|icmp)\s*//) { die "missing proto" if !$pkg->{proto}; return undef if $pkg->{proto} ne $1; # no match next; } if ($rule =~ s/^--dport (\d+):(\d+)\s*//) { die "missing dport" if !$pkg->{dport}; return undef if ($pkg->{dport} < $1) || ($pkg->{dport} > $2); # no match next; } if ($rule =~ s/^--dport (\d+)\s*//) { die "missing dport" if !$pkg->{dport}; return undef if $pkg->{dport} != $1; # no match next; } if ($rule =~ s/^-s (\S+)\s*//) { die "missing source" if !$pkg->{source}; my $ip = Net::IP->new($1); return undef if !$ip->overlaps(Net::IP->new($pkg->{source})); # no match next; } if ($rule =~ s/^-d (\S+)\s*//) { die "missing destination" if !$pkg->{dest}; my $ip = Net::IP->new($1); return undef if !$ip->overlaps(Net::IP->new($pkg->{dest})); # no match next; } if ($rule =~ s/^-m set (!\s+)?--match-set (\S+) src\s*//) { die "missing source" if !$pkg->{source}; my $neg = $1; my $ipset = $ipset_ruleset->{$2}; die "no such ip set '$2'" if !$ipset; if ($neg) { return undef if ipset_match($1, $ipset, $pkg->{source}); } else { return undef if !ipset_match($1, $ipset, $pkg->{source}); } next; } if ($rule =~ s/^-m set --match-set (\S+) dst\s*//) { die "missing destination" if !$pkg->{dest}; my $ipset = $ipset_ruleset->{$1}; die "no such ip set '$1'" if !$ipset; return undef if !ipset_match($1, $ipset, $pkg->{dest}); next; } if ($rule =~ s/^-m mac ! --mac-source (\S+)\s*//) { die "missing source mac" if !$pkg->{mac_source}; return undef if $pkg->{mac_source} eq $1; # no match next; } if ($rule =~ s/^-m physdev --physdev-is-bridged --physdev-in (\S+)\s*//) { my $devre = $1; return undef if !$pkg->{physdev_in}; return undef if !nf_dev_match($devre, $pkg->{physdev_in}); next; } if ($rule =~ s/^-m physdev --physdev-is-bridged --physdev-out (\S+)\s*//) { my $devre = $1; return undef if !$pkg->{physdev_out}; return undef if !nf_dev_match($devre, $pkg->{physdev_out}); next; } if ($rule =~ s/^-m mark --mark (\d+)\s*//) { return undef if !defined($mark) || $mark != $1; next; } # final actions if ($rule =~ s/^-j MARK --set-mark (\d+)\s*$//) { $mark = $1; return undef; } if ($rule =~ s/^-j (\S+)\s*$//) { return (0, $1); } if ($rule =~ s/^-g (\S+)\s*$//) { return (1, $1); } if ($rule =~ s/^-j NFLOG --nflog-prefix \"[^\"]+\"$//) { return undef; } last; } die "unable to parse rule: $rule"; } sub ruleset_simulate_chain { my ($ruleset, $ipset_ruleset, $chain, $pkg) = @_; add_trace("ENTER chain $chain\n"); my $counter = 0; if ($chain eq 'PVEFW-Drop') { add_trace("LEAVE chain $chain\n"); return ('DROP', $counter); } if ($chain eq 'PVEFW-reject') { add_trace("LEAVE chain $chain\n"); return ('REJECT', $counter); } if ($chain eq 'PVEFW-tcpflags') { add_trace("LEAVE chain $chain\n"); return (undef, $counter); } my $rules = $ruleset->{$chain} || die "no such chain '$chain'"; foreach my $rule (@$rules) { $counter++; my ($goto, $action) = rule_match($ipset_ruleset, $chain, $rule, $pkg); if (!defined($action)) { add_trace("SKIP: $rule\n"); next; } add_trace("MATCH: $rule\n"); if ($action eq 'ACCEPT' || $action eq 'DROP' || $action eq 'REJECT') { add_trace("TERMINATE chain $chain: $action\n"); return ($action, $counter); } elsif ($action eq 'RETURN') { add_trace("RETURN FROM chain $chain\n"); last; } else { if ($goto) { add_trace("LEAVE chain $chain - goto $action\n"); return ruleset_simulate_chain($ruleset, $ipset_ruleset, $action, $pkg) #$chain = $action; #$rules = $ruleset->{$chain} || die "no such chain '$chain'"; } else { my ($act, $ctr) = ruleset_simulate_chain($ruleset, $ipset_ruleset, $action, $pkg); $counter += $ctr; return ($act, $counter) if $act; add_trace("CONTINUE chain $chain\n"); } } } add_trace("LEAVE chain $chain\n"); if ($chain =~ m/^PVEFW-(INPUT|OUTPUT|FORWARD)$/) { return ('ACCEPT', $counter); # default policy } return (undef, $counter); } sub copy_packet { my ($pkg) = @_; my $res = {}; while (my ($k,$v) = each %$pkg) { $res->{$k} = $v; } return $res; } # Try to simulate packet traversal inside kernel. This invokes iptable # checks several times. sub route_packet { my ($ruleset, $ipset_ruleset, $pkg, $from_info, $target, $start_state) = @_; my $route_state = $start_state; my $physdev_in; my $ipt_invocation_counter = 0; my $rule_check_counter = 0; while ($route_state ne $target->{iface}) { my $chain; my $next_route_state; my $next_physdev_in; $pkg->{iface_in} = $pkg->{iface_out} = undef; $pkg->{physdev_in} = $pkg->{physdev_out} = undef; if ($route_state eq 'from-bport') { $next_route_state = $from_info->{bridge} || die 'internal error'; $next_physdev_in = $from_info->{iface} || die 'internal error'; } elsif ($route_state eq 'host') { if ($target->{type} eq 'bport') { $pkg->{iface_in} = 'lo'; $pkg->{iface_out} = $target->{bridge} || die 'internal error'; $chain = 'PVEFW-OUTPUT'; $next_route_state = $target->{iface} || die 'internal error'; } elsif ($target->{type} eq 'ct') { $pkg->{iface_in} = 'lo'; $pkg->{iface_out} = 'venet0'; $chain = 'PVEFW-OUTPUT'; $next_route_state = 'venet-in'; } elsif ($target->{type} eq 'vm') { $pkg->{iface_in} = 'lo'; $pkg->{iface_out} = $target->{bridge} || die 'internal error'; $chain = 'PVEFW-OUTPUT'; $next_route_state = 'fwbr-in'; } else { die "implement me"; } } elsif ($route_state eq 'venet-out') { if ($target->{type} eq 'host') { $chain = 'PVEFW-INPUT'; $pkg->{iface_in} = 'venet0'; $pkg->{iface_out} = 'lo'; $next_route_state = 'host'; } elsif ($target->{type} eq 'bport') { $chain = 'PVEFW-FORWARD'; $pkg->{iface_in} = 'venet0'; $pkg->{iface_out} = $target->{bridge} || die 'internal error'; $next_route_state = $target->{iface} || die 'internal error'; } elsif ($target->{type} eq 'vm') { $chain = 'PVEFW-FORWARD'; $pkg->{iface_in} = 'venet0'; $pkg->{iface_out} = $target->{bridge} || die 'internal error'; $next_route_state = 'fwbr-in'; } elsif ($target->{type} eq 'ct') { $chain = 'PVEFW-FORWARD'; $pkg->{iface_in} = 'venet0'; $pkg->{iface_out} = 'venet0'; $next_route_state = 'venet-in'; } else { die "implement me"; } } elsif ($route_state eq 'fwbr-out') { $chain = 'PVEFW-FORWARD'; $next_route_state = $from_info->{bridge} || die 'internal error'; $next_physdev_in = $from_info->{fwpr} || die 'internal error'; $pkg->{iface_in} = $from_info->{fwbr} || die 'internal error'; $pkg->{iface_out} = $from_info->{fwbr} || die 'internal error'; $pkg->{physdev_in} = $from_info->{tapdev} || die 'internal error'; $pkg->{physdev_out} = $from_info->{fwln} || die 'internal error'; } elsif ($route_state eq 'fwbr-in') { $chain = 'PVEFW-FORWARD'; $next_route_state = $target->{tapdev}; $pkg->{iface_in} = $target->{fwbr} || die 'internal error'; $pkg->{iface_out} = $target->{fwbr} || die 'internal error'; $pkg->{physdev_in} = $target->{fwln} || die 'internal error'; $pkg->{physdev_out} = $target->{tapdev} || die 'internal error'; } elsif ($route_state =~ m/^vmbr\d+$/) { die "missing physdev_in - internal error?" if !$physdev_in; $pkg->{physdev_in} = $physdev_in; if ($target->{type} eq 'host') { $chain = 'PVEFW-INPUT'; $pkg->{iface_in} = $route_state; $pkg->{iface_out} = 'lo'; $next_route_state = 'host'; } elsif ($target->{type} eq 'bport') { $chain = 'PVEFW-FORWARD'; $pkg->{iface_in} = $route_state; $pkg->{iface_out} = $target->{bridge} || die 'internal error'; # conditionally set physdev_out (same behavior as kernel) if ($route_state eq $target->{bridge}) { $pkg->{physdev_out} = $target->{iface} || die 'internal error'; } $next_route_state = $target->{iface}; } elsif ($target->{type} eq 'ct') { $chain = 'PVEFW-FORWARD'; $pkg->{iface_in} = $route_state; $pkg->{iface_out} = 'venet0'; $next_route_state = 'venet-in'; } elsif ($target->{type} eq 'vm') { $chain = 'PVEFW-FORWARD'; $pkg->{iface_in} = $route_state; $pkg->{iface_out} = $target->{bridge}; # conditionally set physdev_out (same behavior as kernel) if ($route_state eq $target->{bridge}) { $pkg->{physdev_out} = $target->{fwpr} || die 'internal error'; } $next_route_state = 'fwbr-in'; } else { die "implement me"; } } else { die "implement me $route_state"; } die "internal error" if !defined($next_route_state); if ($chain) { add_trace("IPT check at $route_state (chain $chain)\n"); add_trace(Dumper($pkg)); $ipt_invocation_counter++; my ($res, $ctr) = ruleset_simulate_chain($ruleset, $ipset_ruleset, $chain, $pkg); $rule_check_counter += $ctr; return ($res, $ipt_invocation_counter, $rule_check_counter) if $res ne 'ACCEPT'; } $route_state = $next_route_state; $physdev_in = $next_physdev_in; } return ('ACCEPT', $ipt_invocation_counter, $rule_check_counter); } sub extract_ct_info { my ($vmdata, $vmid) = @_; my $info = { type => 'ct', vmid => $vmid }; my $conf = $vmdata->{openvz}->{$vmid} || die "no such CT '$vmid'"; if ($conf->{ip_address}) { $info->{ip_address} = $conf->{ip_address}->{value}; } else { die "implement me"; } return $info; } sub extract_vm_info { my ($vmdata, $vmid, $netnum) = @_; my $info = { type => 'vm', vmid => $vmid }; my $conf = $vmdata->{qemu}->{$vmid} || die "no such VM '$vmid'"; my $net = PVE::QemuServer::parse_net($conf->{"net$netnum"}); $info->{macaddr} = $net->{macaddr} || die "unable to get mac address"; $info->{bridge} = $net->{bridge} || die "unable to get bridge"; $info->{fwbr} = "fwbr${vmid}i$netnum"; $info->{tapdev} = "tap${vmid}i$netnum"; $info->{fwln} = "fwln${vmid}i$netnum"; $info->{fwpr} = "fwpr${vmid}p$netnum"; return $info; } sub simulate_firewall { my ($ruleset, $ipset_ruleset, $host_ip, $vmdata, $test) = @_; my $from = $test->{from} || die "missing 'from' field"; my $to = $test->{to} || die "missing 'to' field"; my $action = $test->{action} || die "missing 'action'"; my $testid = $test->{id}; die "from/to needs to be different" if $from eq $to; my $pkg = { proto => 'tcp', sport => undef, dport => undef, source => undef, dest => undef, srctype => 'UNICAST', dsttype => 'UNICAST', }; while (my ($k,$v) = each %$test) { next if $k eq 'from'; next if $k eq 'to'; next if $k eq 'action'; next if $k eq 'id'; die "unknown attribute '$k'\n" if !exists($pkg->{$k}); $pkg->{$k} = $v; } my $from_info = {}; my $start_state; if ($from eq 'host') { $from_info->{type} = 'host'; $start_state = 'host'; $pkg->{source} = $host_ip if !defined($pkg->{source}); } elsif ($from =~ m|^(vmbr\d+)/(\S+)$|) { $from_info->{type} = 'bport'; $from_info->{bridge} = $1; $from_info->{iface} = $2; $start_state = 'from-bport'; } elsif ($from eq 'outside') { $from_info->{type} = 'bport'; $from_info->{bridge} = 'vmbr0'; $from_info->{iface} = 'eth0'; $start_state = 'from-bport'; } elsif ($from eq 'nfvm') { $from_info->{type} = 'bport'; $from_info->{bridge} = 'vmbr0'; $from_info->{iface} = 'tapXYZ'; $start_state = 'from-bport'; } elsif ($from =~ m/^ct(\d+)$/) { my $vmid = $1; $from_info = extract_ct_info($vmdata, $vmid); if ($from_info->{ip_address}) { $pkg->{source} = $from_info->{ip_address} if !defined($pkg->{source}); $start_state = 'venet-out'; } else { die "implement me"; } } elsif ($from =~ m/^vm(\d+)(i(\d))?$/) { my $vmid = $1; my $netnum = $3 || 0; $from_info = extract_vm_info($vmdata, $vmid, $netnum); $start_state = 'fwbr-out'; $pkg->{mac_source} = $from_info->{macaddr}; } else { die "unable to parse \"from => '$from'\"\n"; } my $target; if ($to eq 'host') { $target->{type} = 'host'; $target->{iface} = 'host'; $pkg->{dest} = $host_ip if !defined($pkg->{dest}); } elsif ($to =~ m|^(vmbr\d+)/(\S+)$|) { $target->{type} = 'bport'; $target->{bridge} = $1; $target->{iface} = $2; } elsif ($to eq 'outside') { $target->{type} = 'bport'; $target->{bridge} = 'vmbr0'; $target->{iface} = 'eth0'; } elsif ($to eq 'nfvm') { $target->{type} = 'bport'; $target->{bridge} = 'vmbr0'; $target->{iface} = 'tapXYZ'; } elsif ($to =~ m/^ct(\d+)$/) { my $vmid = $1; $target = extract_ct_info($vmdata, $vmid); $target->{iface} = 'venet-in'; if ($target->{ip_address}) { $pkg->{dest} = $target->{ip_address}; } else { die "implement me"; } } elsif ($to =~ m/^vm(\d+)$/) { my $vmid = $1; $target = extract_vm_info($vmdata, $vmid, 0); $target->{iface} = $target->{tapdev}; } else { die "unable to parse \"to => '$to'\"\n"; } $pkg->{source} = '100.100.1.2' if !defined($pkg->{source}); $pkg->{dest} = '100.200.3.4' if !defined($pkg->{dest}); my ($res, $ic, $rc) = route_packet($ruleset, $ipset_ruleset, $pkg, $from_info, $target, $start_state); add_trace("IPT statistics: invocation = $ic, checks = $rc\n"); return $res if $action eq 'QUERY'; die "test failed ($res != $action)\n" if $action ne $res; return undef; } 1;