4 # ferm, a firewall setup program that makes firewall rules easy!
6 # Copyright 2001-2017 Max Kellermann, Auke Kok
8 # Bug reports and patches for this program may be sent to the GitHub
9 # repository: L<https://github.com/MaxKellermann/ferm>
13 # This program is free software; you can redistribute it and/or modify
14 # it under the terms of the GNU General Public License as published by
15 # the Free Software Foundation; either version 2 of the License, or
16 # (at your option) any later version.
18 # This program is distributed in the hope that it will be useful,
19 # but WITHOUT ANY WARRANTY; without even the implied warranty of
20 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
21 # GNU General Public License for more details.
23 # You should have received a copy of the GNU General Public License
24 # along with this program; if not, write to the Free Software
25 # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
34 eval { require strict
; import strict
; };
37 # we need no vars.pm if there is not even strict.pm
39 *vars
::import
= sub {};
44 eval { require Getopt
::Long
; import Getopt
::Long
; };
48 use vars
qw($has_strict $has_getopt);
50 use vars qw($VERSION);
55 ## interface variables
56 # %option = command line and other options
60 use vars qw(@pre_hooks @post_hooks @flush_hooks);
63 # $script: current script file
64 # @stack = ferm's parser stack containing local variables
65 # $auto_chain = index for the next auto-generated chain
66 use vars qw($script @stack $auto_chain);
68 ## netfilter variables
69 # %domains = state information about all domains ("ip" and "ip6")
70 # - initialized: domain initialization is done
71 # - tools: hash providing the paths of the domain's tools
72 # - previous: save file of the previous ruleset, for rollback
73 # - tables{$name}: ferm state information about tables
74 # - has_builtin: whether built-in chains have been determined in this table
75 # - chains{$chain}: ferm state information about the chains
76 # - builtin: whether this is a built-in chain
77 use vars qw(%domains);
80 use vars qw(%deprecated_keywords);
82 # keywords from ferm 1.1 which are deprecated, and the new one; these
83 # are automatically replaced, and a warning is printed
84 %deprecated_keywords = ( realgoto => 'goto',
87 # these hashes provide the Netfilter module definitions
88 use vars qw(%proto_defs %match_defs %target_defs);
91 # This subsubsystem allows you to support (most) new netfilter modules
92 # in ferm. Add a call to one of the "add_XY_def()" functions below.
94 # Ok, now about the cryptic syntax: the function "add_XY_def()"
95 # registers a new module. There are three kinds of modules: protocol
96 # module (e.g. TCP, ICMP), match modules (e.g. state, physdev) and
97 # target modules (e.g. DNAT, MARK).
99 # The first parameter is always the module name which is passed to
100 # iptables with "-p", "-m" or "-j" (depending on which kind of module
103 # After that, you add an encoded string for each option the module
104 # supports. This is where it becomes tricky.
106 # foo defaults to an option with one argument (which may be a ferm
109 # foo*0 option without any arguments
111 # foo=s one argument which must not be a ferm array ('s' stands for
114 # u32=m an array which renders into multiple iptables options in one
117 # ctstate=c one argument, if it's an array, pass it to iptables as a
118 # single comma separated value; example:
119 # ctstate (ESTABLISHED RELATED) translates to:
120 # --ctstate ESTABLISHED,RELATED
122 # foo=sac three arguments: scalar, array, comma separated; you may
123 # concatenate more than one letter code after the '='
125 # foo&bar one argument; call the perl function '&bar()' which parses
128 # !foo negation is allowed and the '!' is written before the keyword
130 # foo! same as above, but '!' is after the keyword and before the
133 # to:=to-destination makes "to" an alias for "to-destination"; you have
134 # to add a declaration for option "to-destination"
137 # prototype declarations
147 # add a module definition
150 my $domain_family = shift;
151 my $params_default = shift;
153 die if exists $defs->{$domain_family}{$name};
154 my $def = $defs->{$domain_family}{$name} = {};
159 if ($keyword =~ s,:=(\S+)$,,) {
160 $k = $def->{keywords}{$1} || die;
161 $k->{ferm_name} ||= $keyword;
163 my $params = $params_default;
164 $params = $1 if $keyword =~ s,\*(\d+)$,,;
165 $params = $1 if $keyword =~ s,=([acs]+|m)$,,;
166 if ($keyword =~ s,&(\S+)$,,) {
167 $params = eval "\\&$1";
172 $k->{params} = $params if $params;
174 $k->{negation} = $k->{pre_negation} = 1 if $keyword =~ s,^!,,;
175 $k->{negation} = 1 if $keyword =~ s,!$,,;
176 $k->{name} = $keyword;
179 $def->{keywords}{$keyword} = $k;
185 # add a protocol module definition
186 sub add_proto_def_x(@) {
187 my $domain_family = shift;
188 add_def_x(\%proto_defs, $domain_family, 1, @_);
191 # add a match module definition
192 sub add_match_def_x(@) {
193 my $domain_family = shift;
194 add_def_x(\%match_defs, $domain_family, 1, @_);
197 # add a target module definition
198 sub add_target_def_x(@) {
199 my $domain_family = shift;
200 add_def_x(\%target_defs, $domain_family, 's', @_);
205 add_def_x($defs, 'ip', @_);
208 # add a protocol module definition
209 sub add_proto_def(@) {
210 add_def(\%proto_defs, 1, @_);
213 # add a match module definition
214 sub add_match_def(@) {
215 add_def(\%match_defs, 1, @_);
218 # add a target module definition
219 sub add_target_def(@) {
220 add_def(\%target_defs, 's', @_);
223 add_proto_def 'dccp', qw(dccp-types!=c dccp-option!);
224 add_proto_def
'mh', qw(mh-type!);
225 add_proto_def
'icmp', qw(icmp-type! icmpv6-type:=icmp-type);
226 add_proto_def
'sctp', qw(chunk-types!=sc);
227 add_proto_def
'tcp', qw(tcp-flags!=cc !syn*0 tcp-option! mss);
228 add_proto_def
'udp', qw();
231 # --source, --destination
232 qw(source!&address_magic saddr:=source),
233 qw(destination!&address_magic daddr:=destination),
235 qw(in-interface! interface:=in-interface if:=in-interface),
237 qw(out-interface! outerface:=out-interface of:=out-interface),
240 add_match_def
'account', qw(aaddr=s aname=s ashort*0);
241 add_match_def
'addrtype', qw(!src-type !dst-type),
242 qw(limit-iface-in*0 limit-iface-out*0);
243 add_match_def
'ah', qw(ahspi! ahlen! ahres*0);
244 add_match_def
'bpf', qw(bytecode);
245 add_match_def
'comment', qw(comment=s);
246 add_match_def
'condition', qw(condition!);
247 add_match_def
'connbytes', qw(!connbytes connbytes-dir connbytes-mode);
248 add_match_def
'connlabel', qw(!label set*0);
249 add_match_def
'connlimit', qw(!connlimit-upto !connlimit-above connlimit-mask connlimit-saddr*0 connlimit-daddr*0);
250 add_match_def
'connmark', qw(!mark);
251 add_match_def
'conntrack', qw(!ctstate=c !ctproto ctorigsrc! ctorigdst! ctorigsrcport! ctorigdstport!),
252 qw(ctreplsrc! ctrepldst! !ctstatus !ctexpire=s ctdir=s);
253 add_match_def
'cpu', qw(!cpu);
254 add_match_def
'devgroup', qw(!src-group !dst-group);
255 add_match_def
'dscp', qw(dscp dscp-class);
256 add_match_def
'dst', qw(!dst-len=s dst-opts=c);
257 add_match_def
'ecn', qw(ecn-tcp-cwr*0 ecn-tcp-ece*0 ecn-ip-ect);
258 add_match_def
'esp', qw(espspi!);
259 add_match_def
'eui64';
260 add_match_def
'fuzzy', qw(lower-limit=s upper-limit=s);
261 add_match_def
'geoip', qw(!src-cc=s !dst-cc=s);
262 add_match_def
'hbh', qw(hbh-len! hbh-opts=c);
263 add_match_def
'helper', qw(helper);
264 add_match_def
'hl', qw(hl-eq! hl-lt=s hl-gt=s);
265 add_match_def
'hashlimit', qw(hashlimit=s hashlimit-burst=s hashlimit-mode=c hashlimit-name=s),
266 qw(hashlimit-upto=s hashlimit-above=s),
267 qw(hashlimit-srcmask=s hashlimit-dstmask=s),
268 qw(hashlimit-htable-size=s hashlimit-htable-max=s),
269 qw(hashlimit-htable-expire=s hashlimit-htable-gcinterval=s);
270 add_match_def
'iprange', qw(!src-range !dst-range);
271 add_match_def
'ipv4options', qw(ssrr*0 lsrr*0 no-srr*0 !rr*0 !ts*0 !ra*0 !any-opt*0);
272 add_match_def
'ipv6header', qw(header!=c soft*0);
273 add_match_def
'ipvs', qw(!ipvs*0 !vproto !vaddr !vport vdir !vportctl);
274 add_match_def
'length', qw(length!);
275 add_match_def
'limit', qw(limit=s limit-burst=s);
276 add_match_def
'mac', qw(mac-source!);
277 add_match_def
'mark', qw(!mark);
278 add_match_def
'multiport', qw(source-ports!&multiport_params),
279 qw(destination-ports!&multiport_params ports!&multiport_params);
280 add_match_def
'nth', qw(every counter start packet);
281 add_match_def
'osf', qw(!genre ttl=s log=s);
282 add_match_def
'owner', qw(!uid-owner !gid-owner pid-owner sid-owner),
283 qw(cmd-owner !socket-exists=0);
284 add_match_def
'physdev', qw(physdev-in! physdev-out!),
285 qw(!physdev-is-in*0 !physdev-is-out*0 !physdev-is-bridged*0);
286 add_match_def
'pkttype', qw(pkt-type!),
287 add_match_def
'policy',
288 qw(dir pol strict*0 !reqid !spi !proto !mode !tunnel-src !tunnel-dst next*0);
289 add_match_def
'psd', qw(psd-weight-threshold psd-delay-threshold),
290 qw(psd-lo-ports-weight psd-hi-ports-weight);
291 add_match_def
'quota', qw(quota=s);
292 add_match_def
'random', qw(average);
293 add_match_def
'realm', qw(realm!);
294 add_match_def
'recent', qw(name=s !set*0 !remove*0 !rcheck*0 !update*0 !seconds !hitcount rttl*0 rsource*0 rdest*0 mask*0);
295 add_match_def
'rpfilter', qw(loose*0 validmark*0 accept-local*0 invert*0);
296 add_match_def
'rt', qw(rt-type! rt-segsleft! rt-len! rt-0-res*0 rt-0-addrs=c rt-0-not-strict*0);
297 add_match_def
'set', qw(!match-set=sc set:=match-set return-nomatch*0 !update-counters*0 !update-subcounters*0 !packets-eq=s packets-lt=s packets-gt=s !bytes-eq=s bytes-lt=s bytes-gt=s);
298 add_match_def
'socket', qw(transparent*0 nowildcard*0 restore-skmark*0);
299 add_match_def
'state', qw(!state=c);
300 add_match_def
'statistic', qw(mode=s probability=s every=s packet=s);
301 add_match_def
'string', qw(algo=s from=s to=s string hex-string);
302 add_match_def
'tcpmss', qw(!mss);
303 add_match_def
'time', qw(timestart=s timestop=s days=c datestart=s datestop=s),
304 qw(!monthday=c !weekdays=c utc*0 localtz*0);
305 add_match_def
'tos', qw(!tos);
306 add_match_def
'ttl', qw(ttl-eq ttl-lt=s ttl-gt=s);
307 add_match_def
'u32', qw(!u32=m);
309 add_target_def
'AUDIT', qw(type);
310 add_target_def
'BALANCE', qw(to-destination to:=to-destination);
311 add_target_def
'CHECKSUM', qw(checksum-fill*0);
312 add_target_def
'CLASSIFY', qw(set-class);
313 add_target_def
'CLUSTERIP', qw(new*0 hashmode clustermac total-nodes local-node hash-init);
314 add_target_def
'CONNMARK', qw(set-xmark save-mark*0 restore-mark*0 nfmask ctmask),
315 qw(and-mark or-mark xor-mark set-mark mask);
316 add_target_def
'CONNSECMARK', qw(save*0 restore*0);
317 add_target_def
'CT', qw(notrack*0 helper ctevents=c expevents=c zone timeout);
318 add_target_def
'DNAT', qw(to-destination=m to:=to-destination persistent*0 random*0);
319 add_target_def
'DNPT', qw(src-pfx dst-pfx);
320 add_target_def
'DSCP', qw(set-dscp set-dscp-class);
321 add_target_def
'ECN', qw(ecn-tcp-remove*0);
322 add_target_def
'HL', qw(hl-set hl-dec hl-inc);
323 add_target_def
'HMARK', qw(hmark-tuple hmark-mod hmark-offset),
324 qw(hmark-src-prefix hmark-dst-prefix hmark-sport-mask),
325 qw(hmark-dport-mask hmark-spi-mask hmark-proto-mask hmark-rnd);
326 add_target_def
'IDLETIMER', qw(timeout label);
327 add_target_def
'IPV4OPTSSTRIP';
328 add_target_def
'LED', qw(led-trigger-id led-delay led-always-blink*0);
329 add_target_def
'LOG', qw(log-level log-prefix),
330 qw(log-tcp-sequence*0 log-tcp-options*0 log-ip-options*0 log-uid*0);
331 add_target_def
'MARK', qw(set-mark set-xmark and-mark or-mark xor-mark);
332 add_target_def
'MASQUERADE', qw(to-ports random*0);
333 add_target_def
'MIRROR';
334 add_target_def
'NETMAP', qw(to);
335 add_target_def
'NFLOG', qw(nflog-group nflog-prefix nflog-range nflog-threshold);
336 add_target_def
'NFQUEUE', qw(queue-num queue-balance queue-bypass*0 queue-cpu-fanout*0);
337 add_target_def
'NOTRACK';
338 add_target_def
'RATEEST', qw(rateest-name rateest-interval rateest-ewmalog);
339 add_target_def
'REDIRECT', qw(to-ports random*0);
340 add_target_def
'REJECT', qw(reject-with);
341 add_target_def
'ROUTE', qw(oif iif gw continue*0 tee*0);
342 add_target_def
'SAME', qw(to nodst*0 random*0);
343 add_target_def
'SECMARK', qw(selctx);
344 add_target_def
'SET', qw(add-set=sc del-set=sc timeout exist*0);
345 add_target_def
'SNAT', qw(to-source=m to:=to-source persistent*0 random*0);
346 add_target_def
'SNPT', qw(src-pfx dst-pfx);
347 add_target_def
'SYNPROXY', qw(sack-perm*0 timestamps*0 ecn*0 wscale=s mss=s);
348 add_target_def
'TARPIT';
349 add_target_def
'TCPMSS', qw(set-mss clamp-mss-to-pmtu*0);
350 add_target_def
'TCPOPTSTRIP', qw(strip-options=c);
351 add_target_def
'TEE', qw(gateway);
352 add_target_def
'TOS', qw(set-tos and-tos or-tos xor-tos);
353 add_target_def
'TPROXY', qw(tproxy-mark on-ip on-port);
354 add_target_def
'TRACE';
355 add_target_def
'TTL', qw(ttl-set ttl-dec ttl-inc);
356 add_target_def
'ULOG', qw(ulog-nlgroup ulog-prefix ulog-cprange ulog-qthreshold);
358 add_match_def_x
'arp', '',
360 qw(source-ip! destination-ip! saddr:=source-ip daddr:=destination-ip),
362 qw(source-mac! destination-mac!),
364 qw(in-interface! interface:=in-interface if:=in-interface),
366 qw(out-interface! outerface:=out-interface of:=out-interface),
368 qw(h-length=s opcode=s h-type=s proto-type=s),
369 qw(mangle-ip-s=s mangle-ip-d=s mangle-mac-s=s mangle-mac-d=s mangle-target=s);
371 add_proto_def_x
'eb', 'IPv4',
372 qw(ip-source! ip-destination! ip-src:=ip-source ip-dst:=ip-destination),
374 qw(ip-protocol! ip-proto:=ip-protocol),
375 qw(ip-source-port! ip-sport:=ip-source-port),
376 qw(ip-destination-port! ip-dport:=ip-destination-port);
378 add_proto_def_x
'eb', 'IPv6',
379 qw(ip6-source! ip6-destination! ip6-src:=ip6-source ip6-dst:=ip6-destination),
381 qw(ip6-protocol! ip6-proto:=ip6-protocol),
382 qw(ip6-source-port! ip6-sport:=ip6-source-port),
383 qw(ip6-destination-port! ip6-dport:=ip6-destination-port);
385 add_proto_def_x
'eb', 'ARP',
386 qw(!arp-gratuitous*0),
387 qw(arp-opcode! arp-htype!=ss arp-ptype!=ss),
388 qw(arp-ip-src! arp-ip-dst! arp-mac-src! arp-mac-dst!);
390 add_proto_def_x
'eb', 'RARP',
391 qw(!arp-gratuitous*0),
392 qw(arp-opcode! arp-htype!=ss arp-ptype!=ss),
393 qw(arp-ip-src! arp-ip-dst! arp-mac-src! arp-mac-dst!);
395 add_proto_def_x
'eb', '802_1Q',
396 qw(vlan-id! vlan-prio! vlan-encap!),
398 add_match_def_x
'eb', '',
400 qw(in-interface! interface:=in-interface if:=in-interface),
402 qw(out-interface! outerface:=out-interface of:=out-interface),
404 qw(logical-in! logical-out!),
405 # --source, --destination
406 qw(source! saddr:=source destination! daddr:=destination),
408 qw(802_3-sap! 802_3-type!),
410 qw(!among-dst=c !among-src=c !among-dst-file !among-src-file),
412 qw(limit=s limit-burst=s),
418 qw(stp-type! stp-flags! stp-root-prio! stp-root-addr! stp-root-cost!),
419 qw(stp-sender-prio! stp-sender-addr! stp-port! stp-msg-age! stp-max-age!),
420 qw(stp-hello-time! stp-forward-delay!),
422 qw(log*0 log-level=s log-prefix=s log-ip*0 log-arp*0);
424 add_target_def_x
'eb', 'arpreply', qw(arpreply-mac arpreply-target);
425 add_target_def_x
'eb', 'dnat', qw(to-destination dnat-target);
426 add_target_def_x
'eb', 'MARK', qw(set-mark mark-target);
427 add_target_def_x
'eb', 'redirect', qw(redirect-target);
428 add_target_def_x
'eb', 'snat', qw(to-source snat-target snat-arp*0);
430 # import-ferm uses the above tables
431 return 1 if $0 =~ /import-ferm$/;
433 # parameter parser for ipt_multiport
434 sub multiport_params
{
437 # multiport only allows 15 ports at a time. For this
438 # reason, we do a little magic here: split the ports
439 # into portions of 15, and handle these portions as
442 my $proto = $rule->{protocol
};
443 error
('To use multiport, you have to specify "proto tcp" or "proto udp" first')
444 unless defined $proto and grep { /^(?:tcp|udp|udplite)$/ } to_array
($proto);
446 my $value = getvalues
(undef, allow_negation
=> 1,
447 allow_array_negation
=> 1);
448 if (ref $value and ref $value eq 'ARRAY') {
453 push @params, join(',', splice(@value, 0, 15));
460 return join_value
(',', $value);
467 # very crude IPv4/IPv6 address detection
468 if ($domain eq 'ip') {
469 @ips = grep { !/:[0-9a-f]*:/ } @_;
470 } elsif ($domain eq 'ip6') {
471 @ips = grep { !m
,^[0-9./]+$,s
} @_;
478 my $domain = $rule->{domain
};
479 my $value = getvalues
(undef, allow_negation
=> 1);
483 if (ref $value and ref $value eq 'ARRAY') {
485 } elsif (ref $value and ref $value eq 'negated') {
488 } elsif (ref $value) {
494 # only do magic on domain (ip ip6); do not process on a single-stack rule
495 # as to let admins spot their errors instead of silently ignoring them
496 @ips = ipfilter
($domain, @ips) if defined $rule->{domain_both
};
498 if ($negated && scalar @ips) {
499 return bless \
@ips, 'negated';
505 # initialize stack: command line definitions
508 # Get command line stuff
510 my ($opt_noexec, $opt_flush, $opt_noflush, $opt_lines, $opt_interactive,
511 $opt_timeout, $opt_help,
512 $opt_version, $opt_test, $opt_fast, $opt_slow, $opt_shell,
515 Getopt
::Long
::Configure
('bundling', 'auto_help', 'no_ignore_case',
519 my ($opt, $value) = @_;
520 die 'Invalid --def specification'
521 unless $value =~ /^\$?(\w+)=(.*)$/s;
522 my ($name, $unparsed_value) = ($1, $2);
523 my $tokens = tokenize_string
($unparsed_value);
524 $value = getvalues
(sub { shift @
$tokens; });
525 die 'Extra tokens after --def'
527 $stack[0]{vars
}{$name} = $value;
530 local $SIG{__WARN__
} = sub { die $_[0]; };
531 GetOptions
('noexec|n' => \
$opt_noexec,
532 'flush|F' => \
$opt_flush,
533 'noflush' => \
$opt_noflush,
534 'lines|l' => \
$opt_lines,
535 'interactive|i' => \
$opt_interactive,
536 'timeout|t=s' => \
$opt_timeout,
537 'help|h' => \
$opt_help,
538 'version|V' => \
$opt_version,
540 remote
=> \
$opt_test,
543 shell
=> \
$opt_shell,
544 'domain=s' => \
$opt_domain,
545 'def=s' => \
&opt_def
,
548 if (defined $opt_help) {
550 Pod
::Usage
::pod2usage
(-exitstatus
=> 0);
553 if (defined $opt_version) {
558 $option{noexec
} = $opt_noexec || $opt_test;
559 $option{flush
} = $opt_flush;
560 $option{noflush
} = $opt_noflush;
561 $option{lines
} = $opt_lines || $opt_test || $opt_shell;
562 $option{interactive
} = $opt_interactive && !$opt_noexec;
563 $option{timeout
} = defined $opt_timeout ?
$opt_timeout : "30";
564 $option{test
} = $opt_test;
565 $option{fast
} = !$opt_slow;
566 $option{shell
} = $opt_shell;
568 die("ferm interactive mode not possible: /dev/stdin is not a tty\n")
569 if $option{interactive
} and not -t STDIN
;
570 die("ferm interactive mode not possible: /dev/stderr is not a tty\n")
571 if $option{interactive
} and not -t STDERR
;
572 die("ferm timeout has no sense without interactive mode")
573 if not $opt_interactive and defined $opt_timeout;
574 die("invalid timeout. must be an integer")
575 if defined $opt_timeout and not $opt_timeout =~ /^[+-]?\d+$/;
577 $option{domain
} = $opt_domain if defined $opt_domain;
579 # tiny getopt emulation for microperl
582 if ($_ eq '--noexec' or $_ eq '-n') {
584 } elsif ($_ eq '--lines' or $_ eq '-l') {
586 } elsif ($_ eq '--fast') {
588 } elsif ($_ eq '--test') {
592 } elsif ($_ eq '--shell') {
593 $option{$_} = 1 foreach qw(shell fast lines);
595 printf STDERR
"Usage: ferm [--noexec] [--lines] [--fast] [--shell] FILENAME\n";
602 push @ARGV, $filename;
605 unless (@ARGV == 1) {
607 Pod
::Usage
::pod2usage
(-exitstatus
=> 1);
611 open LINES
, ">&STDOUT" if $option{lines
};
612 open STDOUT
, ">&STDERR" if $option{shell
};
614 # microperl can't redirect file handles
617 if ($option{fast
} and not $option{noexec
}) {
618 print STDERR
"Sorry, ferm on microperl does not allow --fast without --noexec\n";
624 open_script
($ARGV[0]);
626 my( $volume,$dirs,$file ) = File
::Spec
->splitpath( $ARGV[0] );
627 $stack[0]{auto
}{FILENAME
} = $ARGV[0];
628 $stack[0]{auto
}{FILEBNAME
} = $file;
629 $stack[0]{auto
}{DIRNAME
} = $dirs;
633 # parse all input recursively
635 die unless @stack == 2;
637 # enable/disable hooks depending on --flush
639 if ($option{flush
}) {
646 # execute all generated rules
649 foreach my $cmd (@pre_hooks) {
650 print LINES
"$cmd\n" if $option{lines
};
651 system($cmd) unless $option{noexec
};
654 while (my ($domain, $domain_info) = each %domains) {
655 next unless $domain_info->{enabled
};
656 my $s = $option{fast
} &&
657 defined $domain_info->{tools
}{'tables-restore'}
658 ? execute_fast
($domain_info) : execute_slow
($domain_info);
659 $status = $s if defined $s;
662 foreach my $cmd (@post_hooks, @flush_hooks) {
663 print LINES
"$cmd\n" if $option{lines
};
664 system($cmd) unless $option{noexec
};
667 if (defined $status) {
672 # ask user, and rollback if there is no confirmation
674 if ($option{interactive
}) {
675 if ($option{shell
}) {
676 print LINES
"echo 'ferm has applied the new firewall rules.'\n";
677 print LINES
"echo 'Please press Ctrl-C to confirm.'\n";
678 print LINES
"sleep $option{timeout}\n";
679 while (my ($domain, $domain_info) = each %domains) {
680 my $restore = $domain_info->{tools
}{'tables-restore'};
681 next unless defined $restore;
682 print LINES
"$restore <\$${domain}_tmp\n";
686 confirm_rules
() or rollback
() unless $option{noexec
};
691 # end of program execution!
697 print "ferm $VERSION\n";
698 print "Copyright 2001-2017 Max Kellermann, Auke Kok\n";
699 print "This program is free software released under GPLv2.\n";
700 print "See the included COPYING file for license details.\n";
705 # returns a nice formatted error message, showing the
706 # location of the error.
710 my @words = map { @
$_ } @
{$script->{past_tokens
}};
712 for my $w ( 0 .. $#words ) {
713 if ($words[$w] eq "\x29")
714 { $l++ ; $lines[$l] = " " x
($tabs-- -1) ;};
715 if ($words[$w] eq "\x28")
716 { $l++ ; $lines[$l] = " " x
$tabs++ ;};
717 if ($words[$w] eq "\x7d")
718 { $l++ ; $lines[$l] = " " x
($tabs-- -1) ;};
719 if ($words[$w] eq "\x7b")
720 { $l++ ; $lines[$l] = " " x
$tabs++ ;};
721 if ( $l > $#lines ) { $lines[$l] = "" };
722 $lines[$l] .= $words[$w] . " ";
723 if ($words[$w] eq "\x28")
724 { $l++ ; $lines[$l] = " " x
$tabs ;};
725 if (($words[$w] eq "\x29") && ($words[$w+1] ne "\x7b"))
726 { $l++ ; $lines[$l] = " " x
$tabs ;};
727 if ($words[$w] eq "\x7b")
728 { $l++ ; $lines[$l] = " " x
$tabs ;};
729 if (($words[$w] eq "\x7d") && ($words[$w+1] ne "\x7d"))
730 { $l++ ; $lines[$l] = " " x
$tabs ;};
731 if (($words[$w] eq "\x3b") && ($words[$w+1] ne "\x7d"))
732 { $l++ ; $lines[$l] = " " x
$tabs ;}
733 if ($words[$w-1] eq "option")
734 { $l++ ; $lines[$l] = " " x
$tabs ;}
736 my $start = $#lines - 4;
737 if ($start < 0) { $start = 0 } ;
738 print STDERR
"Error in $script->{filename} line $script->{line}:\n";
739 for $l ( $start .. $#lines)
740 { print STDERR
$lines[$l]; if ($l != $#lines ) {print STDERR
"\n"} ; };
741 print STDERR
"<--\n";
745 # print a warning message about code from an input file
747 print STDERR
"Warning in $script->{filename} line $script->{line}: "
753 return $name if $option{test
};
754 for my $path ('/sbin', split ':', $ENV{PATH
}) {
755 my $ret = "$path/$name";
756 return $ret if -x
$ret;
758 die "$name not found in PATH\n";
761 sub initialize_domain
{
763 my $domain_info = $domains{$domain} ||= {};
765 return if exists $domain_info->{initialized
};
767 die "Invalid domain '$domain'\n" unless $domain =~ /^(?:ip6?|arp|eb)$/;
769 my @tools = qw(tables);
770 push @tools, qw(tables-save tables-restore)
771 if $domain =~ /^ip6?$/;
773 # determine the location of this domain's tools
774 my %tools = map { $_ => find_tool
($domain . $_) } @tools;
775 $domain_info->{tools
} = \
%tools;
777 # make tables-save tell us about the state of this domain
778 # (which tables and chains do exist?), also remember the old
779 # save data which may be used later by the rollback function
781 if (!$option{test
} &&
782 exists $tools{'tables-save'} &&
783 open(SAVE
, "$tools{'tables-save'}|")) {
792 $table_info = $domain_info->{tables
}{$table} ||= {};
793 } elsif (defined $table_info and /^:(\w+)\s+(\S+)/
795 $table_info->{chains
}{$1}{builtin
} = 1;
796 $table_info->{has_builtin
} = 1;
801 $domain_info->{previous
} = $save;
804 if ($option{shell
} && $option{interactive
} &&
805 exists $tools{'tables-save'}) {
806 print LINES
"${domain}_tmp=\$(mktemp ferm.XXXXXXXXXX)\n";
807 print LINES
"$tools{'tables-save'} >\$${domain}_tmp\n";
810 $domain_info->{initialized
} = 1;
813 sub check_domain
($) {
817 return if exists $option{domain
}
818 and $domain ne $option{domain
};
821 initialize_domain
($domain);
828 # split the input string into words and delete comments
829 sub tokenize_string
($) {
834 foreach my $word ($string =~ m/(".*?"|'.*?'|`.*?`|[!,=&\$\%\(\){};]|[-+\w\/\
.:]+|@\w
+|#)/g) {
835 last if $word eq '#';
842 # generate a "line" special token, that marks the line number; these
843 # special tokens are inserted after each line break, so ferm keeps
844 # track of line numbers
845 sub make_line_token
($) {
847 return bless(\
$line, 'line');
850 # read some more tokens from the input file into a buffer
851 sub prepare_tokens
() {
852 my $tokens = $script->{tokens
};
853 while (@
$tokens == 0) {
854 my $handle = $script->{handle
};
855 return unless defined $handle;
856 my $line = <$handle>;
857 return unless defined $line;
859 push @
$tokens, make_line_token
($script->{line
} + 1);
861 # the next parser stage eats this
862 push @
$tokens, @
{tokenize_string
($line)};
868 sub handle_special_token
($) {
870 die unless ref $token;
871 if (ref $token eq 'line') {
872 $script->{line
} = $$token;
878 sub handle_special_tokens
() {
879 my $tokens = $script->{tokens
};
880 while (@
$tokens > 0 and ref $tokens->[0]) {
881 handle_special_token
(shift @
$tokens);
885 # wrapper for prepare_tokens() which handles "special" tokens
886 sub prepare_normal_tokens
() {
887 my $tokens = $script->{tokens
};
889 handle_special_tokens
();
890 return 1 if @
$tokens > 0;
891 return unless prepare_tokens
();
895 # open a ferm sub script
897 my $filename = shift;
899 for (my $s = $script; defined $s; $s = $s->{parent
}) {
900 die("Circular reference in $script->{filename} line $script->{line}: $filename\n")
901 if $s->{filename
} eq $filename;
905 if ($filename eq '-') {
906 # Note that this only allowed in the command-line argument and not
907 # @includes, since those are filtered by collect_filenames()
909 # also set a filename label so that error messages are more helpful
910 $filename = "<stdin>";
913 open FILE
, "$filename" or die("Failed to open $filename: $!\n");
917 $script = { filename
=> $filename,
928 # collect script filenames which are being included
929 sub collect_filenames
(@
) {
932 # determine the current script's parent directory for relative
934 die unless defined $script;
935 my $parent_dir = $script->{filename
} =~ m
,^(.*/),
938 foreach my $pathname (@_) {
939 # non-absolute file names are relative to the parent script's
941 $pathname = $parent_dir . $pathname
942 unless $pathname =~ m
,^/|\
|$,;
944 if ($pathname =~ m
,/$,) {
945 # include all regular files in a directory
947 error
("'$pathname' is not a directory")
951 opendir DIR
, $pathname
952 or error
("Failed to open directory '$pathname': $!");
953 my @names = readdir DIR
;
956 # sort those names for a well-defined order
957 foreach my $name (sort { $a cmp $b } @names) {
958 # ignore dpkg's backup files
959 next if $name =~ /\.dpkg-(old|dist|new|tmp)$/;
960 # don't include hidden and backup files
961 next if $name =~ /^\.|~$/;
963 my $filename = $pathname . $name;
967 } elsif ($pathname =~ m
,\
|$,) {
968 # run a program and use its output
969 push @ret, $pathname;
970 } elsif ($pathname =~ m
,^\
|,) {
971 error
('This kind of pipe is not allowed');
973 # include a regular file
975 error
("'$pathname' is a directory; maybe use trailing '/' to include a directory?")
977 error
("'$pathname' is not a file")
980 push @ret, $pathname;
987 # peek a token from the queue, but don't remove it
989 return unless prepare_normal_tokens
();
990 return $script->{tokens
}[0];
993 # get a token from the queue, including "special" tokens
994 sub next_raw_token
() {
995 return unless prepare_tokens
();
996 return shift @
{$script->{tokens
}};
999 # get a token from the queue
1001 return unless prepare_normal_tokens
();
1002 my $token = shift @
{$script->{tokens
}};
1004 # update $script->{past_tokens}
1005 my $past_tokens = $script->{past_tokens
};
1007 if (@
$past_tokens > 0) {
1008 my $prev_token = $past_tokens->[-1][-1];
1009 $past_tokens->[-1] = @
$past_tokens > 1 ?
['{'] : []
1010 if $prev_token eq ';';
1011 if ($prev_token eq '}') {
1013 $past_tokens->[-1] = $past_tokens->[-1][0] eq '{'
1015 if @
$past_tokens > 0;
1019 push @
$past_tokens, [] if $token eq '{' or @
$past_tokens == 0;
1020 push @
{$past_tokens->[-1]}, $token;
1026 sub expect_token
($;$) {
1029 my $token = next_token
();
1030 error
($msg || "'$expect' expected")
1031 unless defined $token and $token eq $expect;
1034 # require that another token exists, and that it's not a "special"
1035 # token, e.g. ";" and "{"
1036 sub require_next_token
{
1037 my $code = shift || \
&next_token
;
1039 my $token = &$code(@_);
1041 error
('unexpected end of file')
1042 unless defined $token;
1044 error
("'$token' not allowed here")
1045 if $token =~ /^[;{}]$/;
1050 # return the value of a variable
1051 sub variable_value
($) {
1054 if ($name eq "LINE") {
1055 return $script->{line
};
1059 return $_->{vars
}{$name}
1060 if exists $_->{vars
}{$name};
1063 return $stack[0]{auto
}{$name}
1064 if exists $stack[0]{auto
}{$name};
1069 # determine the value of a variable, die if the value is an array
1070 sub string_variable_value
($) {
1072 my $value = variable_value
($name);
1074 error
("variable '$name' must be a string, but it is an array")
1080 # similar to the built-in "join" function, but also handle negated
1081 # values in a special way
1082 sub join_value
($$) {
1083 my ($expr, $value) = @_;
1085 unless (ref $value) {
1087 } elsif (ref $value eq 'ARRAY') {
1088 return join($expr, @
$value);
1089 } elsif (ref $value eq 'negated') {
1090 # bless'negated' is a special marker for negated values
1091 $value = join_value
($expr, $value->[0]);
1092 return bless [ $value ], 'negated';
1098 sub negate_value
($$;$) {
1099 my ($value, $class, $allow_array) = @_;
1102 error
('double negation is not allowed')
1103 if ref $value eq 'negated' or ref $value eq 'pre_negated';
1105 error
('it is not possible to negate an array')
1106 if ref $value eq 'ARRAY' and not $allow_array;
1109 return bless [ $value ], $class || 'negated';
1112 sub format_bool
($) {
1113 return $_[0] ?
1 : 0;
1117 my ($resolver, $names, $type) = @_;
1120 foreach my $hostname (@
$names) {
1121 if (($type eq 'A' and $hostname =~ /^\d+\.\d+\.\d+\.\d+$/) or
1122 (($type eq 'AAAA' and
1123 $hostname =~ /^[0-9a-fA-F:]*:[0-9a-fA-F:]*$/))) {
1124 push @result, $hostname;
1128 my $query = $resolver->search($hostname, $type);
1129 error
("DNS query for '$hostname' failed: " . $resolver->errorstring)
1132 foreach my $rr ($query->answer) {
1133 next unless $rr->type eq $type;
1135 if ($type eq 'NS') {
1136 push @result, $rr->nsdname;
1137 } elsif ($type eq 'MX') {
1138 push @result, $rr->exchange;
1140 push @result, $rr->address;
1145 # NS/MX records return host names; resolve these again in the
1146 # second pass (IPv4 only currently)
1147 @result = resolve
($resolver, @result, 'A')
1148 if $type eq 'NS' or $type eq 'MX';
1153 sub lookup_function
($) {
1157 return $_->{functions
}{$name}
1158 if exists $_->{functions
}{$name};
1164 # returns the next parameter, which may either be a scalar or an array
1169 my $token = require_next_token
($code);
1171 if ($token eq '(') {
1172 # read an array until ")"
1176 $token = getvalues
($code,
1177 parenthesis_allowed
=> 1,
1178 comma_allowed
=> 1);
1180 unless (ref $token) {
1181 last if $token eq ')';
1183 if ($token eq ',') {
1184 error
('Comma is not allowed within arrays, please use only a space');
1188 push @wordlist, $token;
1189 } elsif (ref $token eq 'ARRAY') {
1190 push @wordlist, @
$token;
1192 error
('unknown token type');
1196 error
('empty array not allowed here')
1197 unless @wordlist or not $options{non_empty
};
1199 return @wordlist == 1
1202 } elsif ($token =~ /^\`(.*)\`$/s) {
1203 # execute a shell command, insert output
1205 my $output = `$command`;
1208 error
("failed to execute: $!");
1209 } elsif ($?
& 0x7f) {
1210 error
("child died with signal " . ($?
& 0x7f));
1212 error
("child exited with status " . ($?
>> 8));
1217 $output =~ s/#.*//mg;
1220 my @tokens = grep { length } split /\s+/s, $output;
1224 my $value = getvalues
(sub { shift @tokens });
1225 push @values, to_array
($value);
1232 } elsif ($token =~ /^\'(.*)\'$/s) {
1233 # single quotes: a string
1235 } elsif ($token =~ /^\"(.*)\"$/s) {
1236 # double quotes: a string with escapes
1238 $token =~ s
,\
$(\w
+),string_variable_value
($1),eg
;
1240 } elsif ($token eq '!') {
1241 error
('negation is not allowed here')
1242 unless $options{allow_negation
};
1244 $token = getvalues
($code);
1246 return negate_value
($token, undef, $options{allow_array_negation
});
1247 } elsif ($token eq ',') {
1249 if $options{comma_allowed
};
1251 error
('comma is not allowed here');
1252 } elsif ($token eq '=') {
1253 error
('equals operator ("=") is not allowed here');
1254 } elsif ($token eq '$') {
1255 my $name = require_next_token
($code);
1256 error
('variable name expected - if you want to concatenate strings, try using double quotes')
1257 unless $name =~ /^\w+$/;
1259 my $value = variable_value
($name);
1261 error
("no such variable: \$$name")
1262 unless defined $value;
1265 } elsif ($token eq '&') {
1266 error
("function calls are not allowed as keyword parameter");
1267 } elsif ($token eq ')' and not $options{parenthesis_allowed
}) {
1268 error
('Syntax error');
1269 } elsif ($token =~ /^@/) {
1270 if ($token eq '@resolve') {
1271 my @params = get_function_params
();
1272 error
('Usage: @resolve((hostname ...), [type])')
1273 unless @params == 1 or @params == 2;
1274 eval { require Net
::DNS
; };
1275 error
('For the @resolve() function, you need the Perl library Net::DNS')
1277 my $type = $params[1] || 'A';
1278 error
('String expected') if ref $type;
1279 my $resolver = new Net
::DNS
::Resolver
;
1280 @params = to_array
($params[0]);
1281 my @result = resolve
($resolver, @params, $type);
1282 return @result == 1 ?
$result[0] : \
@result;
1283 } elsif ($token eq '@defined') {
1284 expect_token
('(', 'function name must be followed by "()"');
1285 my $type = require_next_token
();
1287 my $name = require_next_token
();
1288 error
('variable name expected')
1289 unless $name =~ /^\w+$/;
1291 return defined variable_value
($name);
1292 } elsif ($type eq '&') {
1293 my $name = require_next_token
();
1294 error
('function name expected')
1295 unless $name =~ /^\w+$/;
1297 return defined lookup_function
($name);
1299 error
("'\$' or '&' expected")
1301 } elsif ($token eq '@eq') {
1302 my @params = get_function_params
();
1303 error
('Usage: @eq(a, b)') unless @params == 2;
1304 return format_bool
($params[0] eq $params[1]);
1305 } elsif ($token eq '@ne') {
1306 my @params = get_function_params
();
1307 error
('Usage: @ne(a, b)') unless @params == 2;
1308 return format_bool
($params[0] ne $params[1]);
1309 } elsif ($token eq '@not') {
1310 my @params = get_function_params
();
1311 error
('Usage: @not(a)') unless @params == 1;
1312 return format_bool
(not $params[0]);
1313 } elsif ($token eq '@cat') {
1316 error
('String expected') if ref $_;
1318 } get_function_params
();
1320 } elsif ($token eq '@substr') {
1321 my @params = get_function_params
();
1322 error
('Usage: @substr(string, num, num)') unless @params == 3;
1323 error
('String expected') if ref $params[0] or ref $params[1] or ref $params[2];
1324 return substr($params[0],$params[1],$params[2]);
1325 } elsif ($token eq '@length') {
1326 my @params = get_function_params
();
1327 error
('Usage: @length(string)') unless @params == 1;
1328 error
('String expected') if ref $params[0];
1329 return length($params[0]);
1330 } elsif ($token eq '@basename') {
1331 my @params = get_function_params
();
1332 error
('Usage: @basename(path)') unless @params == 1;
1333 error
('String expected') if ref $params[0];
1334 my($volume,$path,$file) = File
::Spec
->splitpath( $params[0] );
1336 } elsif ($token eq '@dirname') {
1337 my @params = get_function_params
();
1338 error
('Usage: @dirname(path)') unless @params == 1;
1339 error
('String expected') if ref $params[0];
1340 my($volume,$path,$file) = File
::Spec
->splitpath( $params[0] );
1342 } elsif ($token eq '@glob') {
1343 my @params = get_function_params
();
1344 error
('Usage: @glob(string)') unless @params == 1;
1346 # determine the current script's parent directory for relative
1348 die unless defined $script;
1349 my $parent_dir = $script->{filename
} =~ m
,^(.*/),
1354 $path = $parent_dir . $path unless $path =~ m
,^/,;
1356 } to_array
($params[0]);
1357 return @result == 1 ?
$result[0] : \
@result;
1358 } elsif ($token eq '@ipfilter') {
1359 my @params = get_function_params
();
1360 error
('Usage: @ipfilter((ip1 ip2 ...))') unless @params == 1;
1361 my $domain = $stack[0]{auto
}{DOMAIN
};
1362 error
('No domain specified') unless defined $domain;
1363 my @ips = ipfilter
($domain, to_array
($params[0]));
1366 error
("unknown ferm built-in function");
1373 # returns the next parameter, but only allow a scalar
1375 my $token = getvalues
();
1377 error
('array not allowed here')
1378 if ref $token and ref $token eq 'ARRAY';
1383 sub get_function_params
(%) {
1384 expect_token
('(', 'function name must be followed by "()"');
1386 my $token = peek_token
();
1387 if ($token eq ')') {
1388 require_next_token
();
1396 $token = require_next_token
();
1400 error
('"," expected')
1401 unless $token eq ',';
1404 push @params, getvalues
(undef, @_);
1410 # collect all tokens in a flat array reference until the end of the
1411 # command is reached
1412 sub collect_tokens
{
1418 # re-insert a "line" token, because the starting token of the
1419 # current line has been consumed already
1420 push @tokens, make_line_token
($script->{line
});
1423 my $keyword = next_raw_token
();
1424 error
('unexpected end of file within function/variable declaration')
1425 unless defined $keyword;
1428 handle_special_token
($keyword);
1429 } elsif ($keyword =~ /^[\{\(]$/) {
1430 push @level, $keyword;
1431 } elsif ($keyword =~ /^[\}\)]$/) {
1432 my $expected = $keyword;
1433 $expected =~ tr/\}\)/\{\(/;
1434 my $opener = pop @level;
1435 error
("unmatched '$keyword'")
1436 unless defined $opener and $opener eq $expected;
1437 } elsif ($keyword eq ';' and @level == 0) {
1438 push @tokens, $keyword
1439 if $options{include_semicolon
};
1441 if ($options{include_else
}) {
1442 my $token = peek_token
;
1443 next if $token eq '@else';
1449 push @tokens, $keyword;
1452 if $keyword eq '}' and @level == 0;
1459 # returns the specified value as an array. dereference arrayrefs
1462 die unless wantarray;
1464 unless (ref $value) {
1466 } elsif (ref $value eq 'ARRAY') {
1473 # evaluate the specified value as bool
1478 unless (ref $value) {
1480 } elsif (ref $value eq 'ARRAY') {
1487 sub is_netfilter_core_target
($) {
1489 die unless defined $target and length $target;
1490 return grep { $_ eq $target } qw(ACCEPT DROP RETURN QUEUE);
1493 sub is_netfilter_module_target
($$) {
1494 my ($domain_family, $target) = @_;
1495 die unless defined $target and length $target;
1497 return defined $domain_family &&
1498 exists $target_defs{$domain_family} &&
1499 $target_defs{$domain_family}{$target};
1502 sub is_netfilter_builtin_chain
($$) {
1503 my ($table, $chain) = @_;
1505 return grep { $_ eq $chain }
1506 qw(PREROUTING INPUT FORWARD OUTPUT POSTROUTING BROUTING);
1509 sub netfilter_canonical_protocol
($) {
1512 if $proto eq 'ipv6-icmp' or $proto eq 'icmpv6';
1514 if $proto eq 'ipv6-mh';
1518 sub netfilter_protocol_module
($) {
1520 return unless defined $proto;
1522 if $proto eq 'icmpv6';
1526 # escape the string in a way safe for the shell
1527 sub shell_escape
($) {
1530 return $token if $token =~ /^[-_a-zA-Z0-9]+$/s;
1532 if ($option{fast
}) {
1533 # iptables-save/iptables-restore are quite buggy concerning
1534 # escaping and special characters... we're trying our best
1537 $token =~ s
,",\\",g
;
1538 $token = '"' . $token . '"'
1539 if $token =~ /[\s\'\\;&]/s or length($token) == 0;
1542 if $token =~ /^\`.*\`$/;
1543 $token =~ s/'/'\\''/g;
1544 $token = '\'' . $token . '\''
1545 if $token =~ /[\s\"\\;<>&|]/s or length($token) == 0;
1551 # append an option to the shell command line, using information from
1552 # the module definition (see %match_defs etc.)
1553 sub shell_format_option
($$) {
1554 my ($keyword, $value) = @_;
1558 if ((ref $value eq 'negated') || (ref $value eq 'pre_negated')) {
1559 $value = $value->[0];
1564 unless (defined $value) {
1565 $cmd .= " --$keyword";
1566 } elsif (ref $value) {
1567 if (ref $value eq 'params') {
1568 $cmd .= " --$keyword ";
1569 $cmd .= join(' ', map { shell_escape
($_) } @
$value);
1570 } elsif (ref $value eq 'multi') {
1572 $cmd .= " --$keyword " . shell_escape
($_);
1578 $cmd .= " --$keyword " . shell_escape
($value);
1584 sub format_option
($$$) {
1585 my ($domain, $name, $value) = @_;
1587 $value = 'icmpv6' if $domain eq 'ip6' and $name eq 'protocol'
1588 and $value eq 'icmp';
1589 $name = 'icmpv6-type' if $domain eq 'ip6' and $name eq 'icmp-type';
1591 if ($domain eq 'ip6' and $name eq 'reject-with') {
1593 'icmp-net-unreachable' => 'icmp6-no-route',
1594 'icmp-host-unreachable' => 'icmp6-addr-unreachable',
1595 'icmp-port-unreachable' => 'icmp6-port-unreachable',
1596 'icmp-net-prohibited' => 'icmp6-adm-prohibited',
1597 'icmp-host-prohibited' => 'icmp6-adm-prohibited',
1598 'icmp-admin-prohibited' => 'icmp6-adm-prohibited',
1600 $value = $icmp_map{$value} if exists $icmp_map{$value};
1603 return shell_format_option
($name, $value);
1606 sub append_rule
($$) {
1607 my ($chain_rules, $rule) = @_;
1609 my $cmd = join('', map { $_->[2] } @
{$rule->{options
}});
1610 push @
$chain_rules, { rule
=> $cmd,
1611 script
=> $rule->{script
},
1616 my ($domain, $chain_rules, $rule) = (shift, shift, shift);
1617 return append_rule
($chain_rules, $rule) unless @_;
1620 my @values = @
{$option->[1]};
1622 foreach my $value (@values) {
1623 $option->[2] = format_option
($domain, $option->[0], $value);
1624 unfold_rule
($domain, $chain_rules, $rule, @_);
1629 my ($domain, $chain_rules, $rule) = @_;
1632 foreach my $option (@
{$rule->{options
}}) {
1633 if (ref $option->[1] and ref $option->[1] eq 'ARRAY') {
1634 push @unfold, $option
1636 $option->[2] = format_option
($domain, $option->[0], $option->[1]);
1640 unfold_rule
($domain, $chain_rules, $rule, @unfold);
1643 # convert a bunch of internal rule structures in iptables calls,
1644 # unfold arrays during that
1648 my $domain = $rule->{domain
};
1649 my $domain_info = $domains{$domain};
1650 $domain_info->{enabled
} = 1;
1652 foreach my $table (to_array
$rule->{table
}) {
1653 my $table_info = $domain_info->{tables
}{$table} ||= {};
1655 foreach my $chain (to_array
$rule->{chain
}) {
1656 my $chain_rules = $table_info->{chains
}{$chain}{rules
} ||= [];
1657 mkrules2
($domain, $chain_rules, $rule)
1658 if $rule->{has_rule
} and not $option{flush
};
1663 # parse a keyword from a module definition
1664 sub parse_keyword
(\
%$$) {
1665 my ($rule, $def, $negated_ref) = @_;
1667 my $params = $def->{params
};
1672 if ($$negated_ref && exists $def->{pre_negation
}) {
1674 undef $$negated_ref;
1677 unless (defined $params) {
1679 } elsif (ref $params && ref $params eq 'CODE') {
1680 $value = &$params($rule);
1681 } elsif ($params eq 'm') {
1682 $value = bless [ to_array getvalues
() ], 'multi';
1683 } elsif ($params =~ /^[a-z]/) {
1684 if (exists $def->{negation
} and not $negated) {
1685 my $token = peek_token
();
1686 if ($token eq '!') {
1687 require_next_token
();
1693 foreach my $p (split(//, $params)) {
1695 push @params, getvar
();
1696 } elsif ($p eq 'c') {
1697 my @v = to_array getvalues
(undef, non_empty
=> 1);
1698 push @params, join(',', @v);
1704 $value = @params == 1
1706 : bless \
@params, 'params';
1707 } elsif ($params == 1) {
1708 if (exists $def->{negation
} and not $negated) {
1709 my $token = peek_token
();
1710 if ($token eq '!') {
1711 require_next_token
();
1716 $value = getvalues
();
1718 warning
("log-prefix is too long; truncating to 29 characters: '$1'")
1719 if $def->{name
} eq 'log-prefix' && $value =~ s
,^(.{29}).+$,$1,;
1721 if (exists $def->{negation
} and not $negated) {
1722 my $token = peek_token
();
1723 if ($token eq '!') {
1724 require_next_token
();
1729 $value = bless [ map {
1731 } (1..$params) ], 'params';
1734 $value = negate_value
($value, exists $def->{pre_negation
} && 'pre_negated')
1740 sub append_option
(\
%$$) {
1741 my ($rule, $name, $value) = @_;
1742 push @
{$rule->{options
}}, [ $name, $value ];
1745 # parse options of a module
1746 sub parse_option
($\
%$) {
1747 my ($def, $rule, $negated_ref) = @_;
1749 append_option
(%$rule, $def->{name
},
1750 parse_keyword
(%$rule, $def, $negated_ref));
1753 sub copy_on_write
($$) {
1754 my ($rule, $key) = @_;
1755 return unless exists $rule->{cow
}{$key};
1756 $rule->{$key} = {%{$rule->{$key}}};
1757 delete $rule->{cow
}{$key};
1760 sub new_level
(\
%$) {
1761 my ($rule, $prev) = @_;
1764 if (defined $prev) {
1765 # copy data from previous level
1766 $rule->{cow
} = { keywords
=> 1, };
1767 $rule->{keywords
} = $prev->{keywords
};
1768 $rule->{match
} = { %{$prev->{match
}} };
1769 $rule->{options
} = [@
{$prev->{options
}}];
1770 foreach my $key (qw(domain domain_family domain_both table chain protocol has_rule has_action)) {
1771 $rule->{$key} = $prev->{$key}
1772 if exists $prev->{$key};
1776 $rule->{keywords
} = {};
1777 $rule->{match
} = {};
1778 $rule->{options
} = [];
1782 sub merge_keywords
(\
%$) {
1783 my ($rule, $keywords) = @_;
1784 copy_on_write
($rule, 'keywords');
1785 while (my ($name, $def) = each %$keywords) {
1786 $rule->{keywords
}{$name} = $def;
1790 sub set_domain
(\
%$) {
1791 my ($rule, $domain) = @_;
1793 return unless check_domain
($domain);
1796 unless (ref $domain) {
1797 $domain_family = $domain eq 'ip6' ?
'ip' : $domain;
1798 } elsif (@
$domain == 0) {
1799 $domain_family = 'none';
1800 } elsif (grep { not /^ip6?$/s } @
$domain) {
1801 error
('Cannot combine non-IP domains');
1803 $domain_family = 'ip';
1806 $rule->{domain_family
} = $domain_family;
1807 $rule->{keywords
} = $match_defs{$domain_family}{''}{keywords
};
1808 $rule->{cow
}{keywords
} = 1;
1810 $rule->{domain
} = $stack[0]{auto
}{DOMAIN
} = $domain;
1813 sub set_target
(\
%$$) {
1814 my ($rule, $name, $value) = @_;
1815 error
('There can only one action per rule')
1816 if exists $rule->{has_action
};
1817 $rule->{has_action
} = 1;
1818 append_option
(%$rule, $name, $value);
1821 sub set_module_target
(\
%$$) {
1822 my ($rule, $name, $defs) = @_;
1824 if ($name eq 'TCPMSS') {
1825 my $protos = $rule->{protocol
};
1826 error
('No protocol specified before TCPMSS')
1827 unless defined $protos;
1828 foreach my $proto (to_array
$protos) {
1829 error
('TCPMSS not available for protocol "$proto"')
1830 unless $proto eq 'tcp';
1834 # in ebtables, there is both "--mark" and "-j mark"... workaround:
1835 $name = 'mark' if $name eq 'MARK' and $rule->{domain_family
} eq 'eb';
1837 set_target
(%$rule, 'jump', $name);
1838 merge_keywords
(%$rule, $defs->{keywords
});
1841 # the main parser loop: read tokens, convert them into internal rule
1844 my $lev = shift; # current recursion depth
1845 my $prev = shift; # previous rule hash
1847 # enter is the core of the firewall setup, it is a
1848 # simple parser program that recognizes keywords and
1849 # retreives parameters to set up the kernel routing
1852 my $base_level = $script->{base_level
} || 0;
1853 die if $base_level > $lev;
1856 new_level
(%rule, $prev);
1858 # read keywords 1 by 1 and dump into parser
1859 while (defined (my $keyword = next_token
())) {
1860 # check if the current rule should be negated
1861 my $negated = $keyword eq '!';
1863 # negation. get the next word which contains the 'real'
1865 $keyword = getvar
();
1867 error
('unexpected end of file after negation')
1868 unless defined $keyword;
1871 # the core: parse all data
1874 # deprecated keyword?
1875 if (exists $deprecated_keywords{$keyword}) {
1876 my $new_keyword = $deprecated_keywords{$keyword};
1877 warning
("'$keyword' is deprecated, please use '$new_keyword' instead");
1878 $keyword = $new_keyword;
1881 # effectuation operator
1882 if ($keyword eq ';') {
1883 error
('Empty rule before ";" not allowed')
1884 unless $rule{non_empty
};
1886 if ($rule{has_rule
} and not exists $rule{has_action
}) {
1887 # something is wrong when a rule was specified,
1889 error
('No action defined; did you mean "NOP"?');
1892 error
('No chain defined') unless exists $rule{chain
};
1894 $rule{script
} = { filename
=> $script->{filename
},
1895 line
=> $script->{line
},
1900 # and clean up variables set in this level
1901 new_level
(%rule, $prev);
1906 # conditional expression
1907 if ($keyword eq '@if') {
1908 unless (eval_bool
(getvalues
)) {
1910 my $token = peek_token
();
1911 if ($token and $token eq '@else') {
1912 require_next_token
();
1914 new_level
(%rule, $prev);
1921 if ($keyword eq '@else') {
1922 # hack: if this "else" has not been eaten by the "if"
1923 # handler above, we believe it came from an if clause
1924 # which evaluated "true" - remove the "else" part now.
1929 # hooks for custom shell commands
1930 if ($keyword eq 'hook') {
1931 warning
("'hook' is deprecated, use '\@hook'");
1935 if ($keyword eq '@hook') {
1936 error
('"hook" must be the first token in a command')
1937 if exists $rule{domain
};
1939 my $position = getvar
();
1941 if ($position eq 'pre') {
1942 $hooks = \
@pre_hooks;
1943 } elsif ($position eq 'post') {
1944 $hooks = \
@post_hooks;
1945 } elsif ($position eq 'flush') {
1946 $hooks = \
@flush_hooks;
1948 error
("Invalid hook position: '$position'");
1951 push @
$hooks, getvar
();
1957 # recursing operators
1958 if ($keyword eq '{') {
1960 my $old_stack_depth = @stack;
1962 unshift @stack, { auto
=> { %{$stack[0]{auto
} || {}} } };
1965 enter
($lev + 1, \
%rule);
1969 die unless @stack == $old_stack_depth;
1971 # after a block, the command is finished, clear this
1973 new_level
(%rule, $prev);
1978 if ($keyword eq '}') {
1979 error
('Unmatched "}"')
1980 if $lev <= $base_level;
1982 # consistency check: check if they havn't forgotten
1983 # the ';' after the last statement
1984 error
('Missing semicolon before "}"')
1985 if $rule{non_empty
};
1991 # include another file
1992 if ($keyword eq '@include' or $keyword eq 'include') {
1993 # don't call collect_filenames() if the file names
1994 # have been expanded already by @glob()
1995 my @files = peek_token
() eq '@glob'
1996 ? to_array
(getvalues
)
1997 : collect_filenames
(to_array
(getvalues
));
1998 $keyword = next_token
;
1999 error
('Missing ";" - "include FILENAME" must be the last command in a rule')
2000 unless defined $keyword and $keyword eq ';';
2002 foreach my $filename (@files) {
2003 # save old script, open new script
2004 my $old_script = $script;
2005 open_script
($filename);
2006 $script->{base_level
} = $lev + 1;
2009 my $old_stack_depth = @stack;
2014 # include files may set variables for their parent
2015 $stack->{vars
} = ($stack[0]{vars
} ||= {});
2016 $stack->{functions
} = ($stack[0]{functions
} ||= {});
2017 $stack->{auto
} = { %{ $stack[0]{auto
} || {} } };
2020 my( $volume,$dirs,$file ) = File
::Spec
->splitpath( $filename );
2021 $stack->{auto
}{FILENAME
} = $filename;
2022 $stack->{auto
}{FILEBNAME
} = $file;
2023 $stack->{auto
}{DIRNAME
} = $dirs;
2025 unshift @stack, $stack;
2028 enter
($lev + 1, \
%rule);
2030 #check for exit status
2031 error
("'$script->{filename}': exit status is not 0") if not close $script->{handle
};
2035 die unless @stack == $old_stack_depth;
2037 # restore old script
2038 $script = $old_script;
2044 # definition of a variable or function
2045 if ($keyword eq '@def' or $keyword eq 'def') {
2046 error
('"def" must be the first token in a command')
2047 if $rule{non_empty
};
2049 my $type = require_next_token
();
2051 my $name = require_next_token
();
2052 error
('invalid variable name')
2053 unless $name =~ /^\w+$/;
2057 my $value = getvalues
(undef, allow_negation
=> 1);
2061 $stack[0]{vars
}{$name} = $value
2062 unless exists $stack[-1]{vars
}{$name};
2063 } elsif ($type eq '&') {
2064 my $name = require_next_token
();
2065 error
('invalid function name')
2066 unless $name =~ /^\w+$/;
2068 expect_token
('(', 'function parameter list or "()" expected');
2072 my $token = require_next_token
();
2073 last if $token eq ')';
2076 error
('"," expected')
2077 unless $token eq ',';
2079 $token = require_next_token
();
2082 error
('"$" and parameter name expected')
2083 unless $token eq '$';
2085 $token = require_next_token
();
2086 error
('invalid function parameter name')
2087 unless $token =~ /^\w+$/;
2089 push @params, $token;
2094 $function{params
} = \
@params;
2098 my $tokens = collect_tokens
();
2099 $function{block
} = 1 if grep { $_ eq '{' } @
$tokens;
2100 $function{tokens
} = $tokens;
2102 $stack[0]{functions
}{$name} = \
%function
2103 unless exists $stack[-1]{functions
}{$name};
2105 error
('"$" (variable) or "&" (function) expected');
2111 # this rule has something which isn't inherited by its
2112 # parent closure. This variable is used in a lot of
2115 $rule{non_empty
} = 1;
2118 if ($keyword eq '$') {
2119 error
('variable references are only allowed as keyword parameter');
2122 if ($keyword eq '&') {
2123 my $name = require_next_token
();
2124 error
('function name expected')
2125 unless $name =~ /^\w+$/;
2127 my $function = lookup_function
($name);
2128 error
("no such function: \&$name")
2129 unless defined $function;
2131 my $paramdef = $function->{params
};
2132 die unless defined $paramdef;
2134 my @params = get_function_params
(allow_negation
=> 1);
2136 error
("Wrong number of parameters for function '\&$name': "
2137 . @
$paramdef . " expected, " . @params . " given")
2138 unless @params == @
$paramdef;
2141 for (my $i = 0; $i < @params; $i++) {
2142 $vars{$paramdef->[$i]} = $params[$i];
2145 if ($function->{block
}) {
2146 # block {} always ends the current rule, so if the
2147 # function contains a block, we have to require
2148 # the calling rule also ends here
2152 my @tokens = @
{$function->{tokens
}};
2153 for (my $i = 0; $i < @tokens; $i++) {
2154 if ($tokens[$i] eq '$' and $i + 1 < @tokens and
2155 exists $vars{$tokens[$i + 1]}) {
2156 my @value = to_array
($vars{$tokens[$i + 1]});
2157 @value = ('(', @value, ')')
2158 unless @tokens == 1;
2159 splice(@tokens, $i, 2, @value);
2161 } elsif ($tokens[$i] =~ m
,^"(.*)"$,) {
2162 $tokens[$i] =~ s
,\
$(\w
+),exists $vars{$1} ?
$vars{$1} : "\$$1",eg
;
2166 unshift @
{$script->{tokens
}}, @tokens;
2171 # where to put the rule?
2172 if ($keyword eq 'domain') {
2173 error
('Domain is already specified')
2174 if exists $rule{domain
};
2176 my $domains = getvalues
();
2178 my $tokens = collect_tokens
(include_semicolon
=> 1,
2181 my $old_line = $script->{line
};
2182 my $old_handle = $script->{handle
};
2183 my $old_tokens = $script->{tokens
};
2184 my $old_base_level = $script->{base_level
};
2185 unshift @
$old_tokens, make_line_token
($script->{line
});
2186 delete $script->{handle
};
2188 for my $domain (@
$domains) {
2190 new_level
(%inner, \
%rule);
2191 set_domain
(%inner, $domain) or next;
2192 $inner{domain_both
} = 1;
2193 $script->{base_level
} = 0;
2194 $script->{tokens
} = [ @
$tokens ];
2198 $script->{base_level
} = $old_base_level;
2199 $script->{tokens
} = $old_tokens;
2200 $script->{handle
} = $old_handle;
2201 $script->{line
} = $old_line;
2203 new_level
(%rule, $prev);
2205 unless (set_domain
(%rule, $domains)) {
2207 new_level
(%rule, $prev);
2214 if ($keyword eq 'table') {
2215 warning
('Table is already specified')
2216 if exists $rule{table
};
2217 $rule{table
} = $stack[0]{auto
}{TABLE
} = getvalues
();
2219 set_domain
(%rule, $option{domain
} || 'ip')
2220 unless exists $rule{domain
};
2225 if ($keyword eq 'chain') {
2226 warning
('Chain is already specified')
2227 if exists $rule{chain
};
2229 my $chain = $rule{chain
} = $stack[0]{auto
}{CHAIN
} = getvalues
();
2231 # ferm 1.1 allowed lower case built-in chain names
2232 foreach (ref $rule{chain
} ? @
{$rule{chain
}} : $rule{chain
}) {
2233 error
('Please write built-in chain names in upper case')
2234 if /^(?:input|forward|output|prerouting|postrouting)$/;
2237 set_domain
(%rule, $option{domain
} || 'ip')
2238 unless exists $rule{domain
};
2240 $rule{table
} = 'filter'
2241 unless exists $rule{table
};
2243 my $domain = $rule{domain
};
2244 foreach my $table (to_array
$rule{table
}) {
2245 foreach my $c (to_array
$chain) {
2246 $domains{$domain}{tables
}{$table}{chains
}{$c} ||= {};
2253 error
('Chain must be specified')
2254 unless exists $rule{chain
};
2256 # policy for built-in chain
2257 if ($keyword eq 'policy') {
2258 error
('Cannot specify matches for policy')
2261 my $policy = getvar
();
2262 error
("Invalid policy target: $policy")
2263 unless is_netfilter_core_target
($policy);
2267 my $domain = $rule{domain
};
2268 my $domain_info = $domains{$domain};
2269 $domain_info->{enabled
} = 1;
2271 foreach my $table (to_array
$rule{table
}) {
2272 foreach my $chain (to_array
$rule{chain
}) {
2273 $domain_info->{tables
}{$table}{chains
}{$chain}{policy
} = $policy;
2277 new_level
(%rule, $prev);
2282 if ($keyword eq '@subchain' or $keyword eq 'subchain' or $keyword eq '@gotosubchain') {
2283 error
('Chain must be specified')
2284 unless exists $rule{chain
};
2286 my $jumptype = ($keyword =~ /^\@go/) ?
'goto' : 'jump';
2287 my $jumpkey = $keyword;
2288 $jumpkey =~ s/^sub/\@sub/;
2290 error
('No rule specified before $jumpkey')
2291 unless $rule{has_rule
};
2294 my $token = peek_token
();
2296 if ($token =~ /^(["'])(.*)\1$/s) {
2299 $keyword = next_token
();
2300 } elsif ($token eq '{') {
2301 $keyword = next_token
();
2302 $subchain = 'ferm_auto_' . ++$auto_chain;
2304 $subchain = getvar
();
2305 $keyword = next_token
();
2308 my $domain = $rule{domain
};
2309 foreach my $table (to_array
$rule{table
}) {
2310 $domains{$domain}{tables
}{$table}{chains
}{$subchain} ||= {};
2313 set_target
(%rule, $jumptype, $subchain);
2315 error
('"{" or chain name expected after $jumpkey')
2316 unless $keyword eq '{';
2318 # create a deep copy of %rule, only containing values
2319 # which must be in the subchain
2320 my %inner = ( cow
=> { keywords
=> 1, },
2324 $inner{$_} = $rule{$_} foreach qw(domain domain_family domain_both table keywords);
2325 $inner{chain
} = $inner{auto
}{CHAIN
} = $subchain;
2327 if (exists $rule{protocol
}) {
2328 $inner{protocol
} = $rule{protocol
};
2329 append_option
(%inner, 'protocol', $inner{protocol
});
2332 # create a new stack frame
2333 my $old_stack_depth = @stack;
2334 my $stack = { auto
=> { %{$stack[0]{auto
} || {}} } };
2335 $stack->{auto
}{CHAIN
} = $subchain;
2336 unshift @stack, $stack;
2339 enter
($lev + 1, \
%inner);
2343 die unless @stack == $old_stack_depth;
2345 # now handle the parent - it's a jump to the sub chain
2347 filename
=> $script->{filename
},
2348 line
=> $script->{line
},
2353 # and clean up variables set in this level
2354 new_level
(%rule, $prev);
2355 delete $rule{has_rule
};
2360 # everything else must be part of a "real" rule, not just
2362 $rule{has_rule
} = 1;
2364 # extended parameters:
2365 if ($keyword =~ /^mod(?:ule)?$/) {
2366 foreach my $module (to_array getvalues
) {
2367 next if exists $rule{match
}{$module};
2369 my $domain_family = $rule{domain_family
};
2370 my $defs = $match_defs{$domain_family}{$module};
2372 append_option
(%rule, 'match', $module);
2373 $rule{match
}{$module} = 1;
2375 merge_keywords
(%rule, $defs->{keywords
})
2382 # keywords from $rule{keywords}
2384 if (exists $rule{keywords
}{$keyword}) {
2385 my $def = $rule{keywords
}{$keyword};
2386 parse_option
($def, %rule, \
$negated);
2395 if ($keyword eq 'jump') {
2396 set_target
(%rule, 'jump', getvar
());
2401 if ($keyword eq 'goto') {
2402 set_target
(%rule, 'goto', getvar
());
2407 if (is_netfilter_core_target
($keyword)) {
2408 set_target
(%rule, 'jump', $keyword);
2412 if ($keyword eq 'NOP') {
2413 error
('There can only one action per rule')
2414 if exists $rule{has_action
};
2415 $rule{has_action
} = 1;
2419 if (my $defs = is_netfilter_module_target
($rule{domain_family
}, $keyword)) {
2420 set_module_target
(%rule, $keyword, $defs);
2425 # protocol specific options
2428 if ($keyword eq 'proto' or $keyword eq 'protocol') {
2429 my $protocol = parse_keyword
(%rule,
2430 { params
=> 1, negation
=> 1 },
2432 $rule{protocol
} = $protocol;
2433 append_option
(%rule, 'protocol', $rule{protocol
});
2435 unless (ref $protocol) {
2436 $protocol = netfilter_canonical_protocol
($protocol);
2437 my $domain_family = $rule{domain_family
};
2438 if (my $defs = $proto_defs{$domain_family}{$protocol}) {
2439 merge_keywords
(%rule, $defs->{keywords
});
2440 my $module = netfilter_protocol_module
($protocol);
2441 $rule{match
}{$module} = 1;
2448 if ($keyword =~ /^[sd]port$/) {
2449 my $proto = $rule{protocol
};
2450 error
('To use sport or dport, you have to specify "proto tcp" or "proto udp" first')
2451 unless defined $proto and grep { /^(?:tcp|udp|udplite|dccp|sctp)$/ } to_array
$proto;
2453 append_option
(%rule, $keyword,
2454 getvalues
(undef, allow_negation
=> 1));
2459 error
("Unrecognized keyword: $keyword");
2462 # if the rule didn't reset the negated flag, it's not
2464 error
("Doesn't support negation: $keyword")
2468 error
('Missing "}" at end of file')
2469 if $lev > $base_level;
2471 # consistency check: check if they havn't forgotten
2472 # the ';' before the last statement
2473 error
("Missing semicolon before end of file")
2474 if $rule{non_empty
};
2477 sub execute_command
{
2478 my ($command, $script) = @_;
2480 print LINES
"$command\n"
2482 return if $option{noexec
};
2484 my $ret = system($command);
2485 unless ($ret == 0) {
2487 print STDERR
"failed to execute: $!\n";
2489 } elsif ($?
& 0x7f) {
2490 printf STDERR
"child died with signal %d\n", $?
& 0x7f;
2493 print STDERR
"(rule declared in $script->{filename}:$script->{line})\n"
2502 sub execute_slow
($) {
2503 my $domain_info = shift;
2505 my $domain_cmd = $domain_info->{tools
}{tables
};
2508 while (my ($table, $table_info) = each %{$domain_info->{tables
}}) {
2509 my $table_cmd = "$domain_cmd -t $table";
2511 # reset chain policies
2512 while (my ($chain, $chain_info) = each %{$table_info->{chains
}}) {
2513 next unless $chain_info->{builtin
} or
2514 (not $table_info->{has_builtin
} and
2515 is_netfilter_builtin_chain
($table, $chain));
2516 $status ||= execute_command
("$table_cmd -P $chain ACCEPT")
2517 unless $option{noflush
};
2521 unless ($option{noflush
}) {
2522 $status ||= execute_command
("$table_cmd -F");
2523 $status ||= execute_command
("$table_cmd -X");
2526 next if $option{flush
};
2528 # create chains / set policy
2529 while (my ($chain, $chain_info) = each %{$table_info->{chains
}}) {
2530 if (is_netfilter_builtin_chain
($table, $chain)) {
2531 if (exists $chain_info->{policy
}) {
2532 $status ||= execute_command
("$table_cmd -P $chain $chain_info->{policy}")
2533 unless $chain_info->{policy
} eq 'ACCEPT';
2536 if (exists $chain_info->{policy
}) {
2537 $status ||= execute_command
("$table_cmd -N $chain -P $chain_info->{policy}");
2540 $status ||= execute_command
("$table_cmd -N $chain");
2546 while (my ($chain, $chain_info) = each %{$table_info->{chains
}}) {
2547 my $chain_cmd = "$table_cmd -A $chain";
2548 foreach my $rule (@
{$chain_info->{rules
}}) {
2549 $status ||= execute_command
($chain_cmd . $rule->{rule
});
2557 sub table_to_save
($$) {
2558 my ($result_r, $table_info) = @_;
2560 foreach my $chain (sort keys %{$table_info->{chains
}}) {
2561 my $chain_info = $table_info->{chains
}{$chain};
2562 foreach my $rule (@
{$chain_info->{rules
}}) {
2563 $$result_r .= "-A $chain$rule->{rule}\n";
2568 sub rules_to_save
($) {
2569 my ($domain_info) = @_;
2571 # convert this into an iptables-save text
2572 my $result = "# Generated by ferm $VERSION on " . localtime() . "\n";
2574 while (my ($table, $table_info) = each %{$domain_info->{tables
}}) {
2576 $result .= '*' . $table . "\n";
2578 # create chains / set policy
2579 foreach my $chain (sort keys %{$table_info->{chains
}}) {
2580 my $chain_info = $table_info->{chains
}{$chain};
2581 my $policy = $option{flush
} ?
undef : $chain_info->{policy
};
2582 unless (defined $policy) {
2583 if (is_netfilter_builtin_chain
($table, $chain)) {
2586 next if $option{flush
};
2590 $result .= ":$chain $policy\ [0:0]\n";
2593 table_to_save
(\
$result, $table_info)
2594 unless $option{flush
};
2597 $result .= "COMMIT\n";
2603 sub restore_domain
($$) {
2604 my ($domain_info, $save) = @_;
2606 my $path = $domain_info->{tools
}{'tables-restore'};
2607 $path .= " --noflush" if $option{noflush
};
2610 open RESTORE
, "|$path"
2611 or die "Failed to run $path: $!\n";
2613 print RESTORE
$save;
2616 or die "Failed to run $path\n";
2619 sub execute_fast
($) {
2620 my $domain_info = shift;
2622 my $save = rules_to_save
($domain_info);
2624 if ($option{lines
}) {
2625 my $path = $domain_info->{tools
}{'tables-restore'};
2626 $path .= " --noflush" if $option{noflush
};
2627 print LINES
"$path <<EOT\n"
2634 return if $option{noexec};
2637 restore_domain($domain_info, $save);
2649 while (my ($domain, $domain_info) = each %domains) {
2650 next unless $domain_info->{enabled};
2651 unless (defined $domain_info->{tools}{'tables-restore'}) {
2652 print STDERR "Cannot rollback domain
'$domain' because there is
no ${domain
}tables
-restore
\n";
2657 while (my ($table, $table_info) = each %{$domain_info->{tables}}) {
2658 my $reset_chain = '';
2659 foreach my $chain (keys %{$table_info->{chains}}) {
2660 next unless is_netfilter_builtin_chain($table, $chain);
2661 $reset_chain .= ":${chain
} ACCEPT
[0:0]\n";
2663 $reset .= "*${table
}\n${reset_chain
}COMMIT
\n"
2664 if length $reset_chain;
2667 $reset .= $domain_info->{previous}
2668 if defined $domain_info->{previous};
2670 restore_domain($domain_info, $reset);
2673 print STDERR "\nFirewall rules rolled back
.\n" unless $error;
2678 # do nothing, just interrupt a system call
2682 $SIG{ALRM} = \&alrm_handler;
2687 . "ferm has applied the new firewall rules
.\n"
2688 . "Please type
'yes' to confirm
:\n";
2691 alarm($option{timeout});
2694 STDIN->sysread($line, 3);
2698 POSIX::tcflush(*STDIN, 2);
2700 print STDERR "$@
" if $@;
2702 $SIG{ALRM} = 'DEFAULT';
2704 return $line eq 'yes';
2713 ferm - a firewall rule parser for linux
2717 B<ferm> I<options> I<inputfiles>
2721 -n, --noexec Do not execute the rules, just simulate
2722 -F, --flush Flush all netfilter tables managed by ferm
2723 -l, --lines Show all rules that were created
2724 -i, --interactive Interactive mode: revert if user does not confirm
2725 -t, --timeout s Define interactive mode timeout in seconds
2726 --remote Remote mode; ignore host specific configuration.
2727 This implies --noexec and --lines.
2728 -V, --version Show current version number
2729 -h, --help Look at this text
2730 --slow Slow mode, don't use iptables-restore
2731 --shell Generate a shell script which calls iptables-restore
2732 --domain {ip|ip6} Handle only the specified domain
2733 --def '$name=v' Override a variable