Make sure that NOTRACK is linked into firewall3 if it is part of libext*.a
[project/firewall3.git] / iptables.c
1 /*
2  * firewall3 - 3rd OpenWrt UCI firewall implementation
3  *
4  *   Copyright (C) 2013 Jo-Philipp Wich <jow@openwrt.org>
5  *
6  * Permission to use, copy, modify, and/or distribute this software for any
7  * purpose with or without fee is hereby granted, provided that the above
8  * copyright notice and this permission notice appear in all copies.
9  *
10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17  */
18
19 #include "iptables.h"
20
21
22 static struct option base_opts[] = {
23         { .name = "match",  .has_arg = 1, .val = 'm' },
24         { .name = "jump",   .has_arg = 1, .val = 'j' },
25         { NULL }
26 };
27
28 static struct xtables_globals xtg = {
29         .option_offset = 0,
30         .program_version = "4",
31         .orig_opts = base_opts,
32 };
33
34 static struct xtables_globals xtg6 = {
35         .option_offset = 0,
36         .program_version = "6",
37         .orig_opts = base_opts,
38 };
39
40 /* Required by certain extensions like SNAT and DNAT */
41 int kernel_version = 0;
42
43 void
44 get_kernel_version(void)
45 {
46         static struct utsname uts;
47         int x = 0, y = 0, z = 0;
48
49         if (uname(&uts) == -1)
50                 sprintf(uts.release, "3.0.0");
51
52         sscanf(uts.release, "%d.%d.%d", &x, &y, &z);
53         kernel_version = 0x10000 * x + 0x100 * y + z;
54 }
55
56 #ifdef DISABLE_IPV6
57 #undef __ipt_module
58 #define __ipt_module(x) libxt_##x##_init, libipt_##x##_init,
59 #else
60 #undef __ipt_module
61 #define __ipt_module(x) libxt_##x##_init, libipt_##x##_init, libip6t_##x##_init,
62 #endif
63
64 static void fw3_init_extensions(void)
65 {
66         int i;
67         void (*initfuncs[])(void) = { FW3_IPT_MODULES };
68
69         for (i = 0; i < sizeof(initfuncs)/sizeof(initfuncs[0]); i++)
70                 if (initfuncs[i])
71                         initfuncs[i]();
72 }
73
74 struct fw3_ipt_handle *
75 fw3_ipt_open(enum fw3_family family, enum fw3_table table)
76 {
77         struct fw3_ipt_handle *h;
78
79         h = fw3_alloc(sizeof(*h));
80
81         xtables_init();
82
83         if (family == FW3_FAMILY_V6)
84         {
85 #ifndef DISABLE_IPV6
86                 h->family = FW3_FAMILY_V6;
87                 h->table  = table;
88                 h->handle = ip6tc_init(fw3_flag_names[table]);
89
90                 xtables_set_params(&xtg6);
91                 xtables_set_nfproto(NFPROTO_IPV6);
92 #endif
93         }
94         else
95         {
96                 h->family = FW3_FAMILY_V4;
97                 h->table  = table;
98                 h->handle = iptc_init(fw3_flag_names[table]);
99
100                 xtables_set_params(&xtg);
101                 xtables_set_nfproto(NFPROTO_IPV4);
102         }
103
104         if (!h->handle)
105         {
106                 free(h);
107                 return NULL;
108         }
109
110         fw3_xt_reset();
111         fw3_init_extensions();
112
113         return h;
114 }
115
116 static void
117 debug(struct fw3_ipt_handle *h, const char *fmt, ...)
118 {
119         va_list ap;
120
121         printf("%s -t %s ", (h->family == FW3_FAMILY_V6) ? "ip6tables" : "iptables",
122                             fw3_flag_names[h->table]);
123
124         va_start(ap, fmt);
125         vprintf(fmt, ap);
126         va_end(ap);
127 }
128
129 void
130 fw3_ipt_set_policy(struct fw3_ipt_handle *h, const char *chain,
131                    enum fw3_flag policy)
132 {
133         if (fw3_pr_debug)
134                 debug(h, "-P %s %s\n", chain, fw3_flag_names[policy]);
135
136 #ifndef DISABLE_IPV6
137         if (h->family == FW3_FAMILY_V6)
138                 ip6tc_set_policy(chain, fw3_flag_names[policy], NULL, h->handle);
139         else
140 #endif
141                 iptc_set_policy(chain, fw3_flag_names[policy], NULL, h->handle);
142 }
143
144 void
145 fw3_ipt_flush_chain(struct fw3_ipt_handle *h, const char *chain)
146 {
147         if (fw3_pr_debug)
148                 debug(h, "-F %s\n", chain);
149
150 #ifndef DISABLE_IPV6
151         if (h->family == FW3_FAMILY_V6)
152                 ip6tc_flush_entries(chain, h->handle);
153         else
154 #endif
155                 iptc_flush_entries(chain, h->handle);
156 }
157
158 static void
159 delete_rules(struct fw3_ipt_handle *h, const char *target)
160 {
161         unsigned int num;
162         const struct ipt_entry *e;
163         const char *chain;
164         const char *t;
165         bool found;
166
167 #ifndef DISABLE_IPV6
168         if (h->family == FW3_FAMILY_V6)
169         {
170                 for (chain = ip6tc_first_chain(h->handle);
171                      chain != NULL;
172                      chain = ip6tc_next_chain(h->handle))
173                 {
174                         do {
175                                 found = false;
176
177                                 const struct ip6t_entry *e6;
178                                 for (num = 0, e6 = ip6tc_first_rule(chain, h->handle);
179                                          e6 != NULL;
180                                          num++, e6 = ip6tc_next_rule(e6, h->handle))
181                                 {
182                                         t = ip6tc_get_target(e6, h->handle);
183
184                                         if (*t && !strcmp(t, target))
185                                         {
186                                                 if (fw3_pr_debug)
187                                                         debug(h, "-D %s %u\n", chain, num + 1);
188
189                                                 ip6tc_delete_num_entry(chain, num, h->handle);
190                                                 found = true;
191                                                 break;
192                                         }
193                                 }
194                         } while (found);
195                 }
196         }
197         else
198 #endif
199         {
200                 for (chain = iptc_first_chain(h->handle);
201                      chain != NULL;
202                      chain = iptc_next_chain(h->handle))
203                 {
204                         do {
205                                 found = false;
206
207                                 for (num = 0, e = iptc_first_rule(chain, h->handle);
208                                      e != NULL;
209                                          num++, e = iptc_next_rule(e, h->handle))
210                                 {
211                                         t = iptc_get_target(e, h->handle);
212
213                                         if (*t && !strcmp(t, target))
214                                         {
215                                                 if (fw3_pr_debug)
216                                                         debug(h, "-D %s %u\n", chain, num + 1);
217
218                                                 iptc_delete_num_entry(chain, num, h->handle);
219                                                 found = true;
220                                                 break;
221                                         }
222                                 }
223                         } while (found);
224                 }
225         }
226 }
227
228 void
229 fw3_ipt_delete_chain(struct fw3_ipt_handle *h, const char *chain)
230 {
231         delete_rules(h, chain);
232
233         if (fw3_pr_debug)
234                 debug(h, "-X %s\n", chain);
235
236 #ifndef DISABLE_IPV6
237         if (h->family == FW3_FAMILY_V6)
238                 ip6tc_delete_chain(chain, h->handle);
239         else
240 #endif
241                 iptc_delete_chain(chain, h->handle);
242 }
243
244 void
245 fw3_ipt_create_chain(struct fw3_ipt_handle *h, const char *fmt, ...)
246 {
247         char buf[32];
248         va_list ap;
249
250         va_start(ap, fmt);
251         vsnprintf(buf, sizeof(buf) - 1, fmt, ap);
252         va_end(ap);
253
254         if (fw3_pr_debug)
255                 debug(h, "-N %s\n", buf);
256
257         iptc_create_chain(buf, h->handle);
258 }
259
260 void
261 fw3_ipt_flush(struct fw3_ipt_handle *h)
262 {
263         const char *chain;
264
265 #ifndef DISABLE_IPV6
266         if (h->family == FW3_FAMILY_V6)
267         {
268                 for (chain = ip6tc_first_chain(h->handle);
269                      chain != NULL;
270                      chain = ip6tc_next_chain(h->handle))
271                 {
272                         ip6tc_flush_entries(chain, h->handle);
273                 }
274
275                 for (chain = ip6tc_first_chain(h->handle);
276                      chain != NULL;
277                      chain = ip6tc_next_chain(h->handle))
278                 {
279                         ip6tc_delete_chain(chain, h->handle);
280                 }
281         }
282         else
283 #endif
284         {
285                 for (chain = iptc_first_chain(h->handle);
286                      chain != NULL;
287                      chain = iptc_next_chain(h->handle))
288                 {
289                         iptc_flush_entries(chain, h->handle);
290                 }
291
292                 for (chain = iptc_first_chain(h->handle);
293                      chain != NULL;
294                      chain = iptc_next_chain(h->handle))
295                 {
296                         iptc_delete_chain(chain, h->handle);
297                 }
298         }
299 }
300
301 void
302 fw3_ipt_commit(struct fw3_ipt_handle *h)
303 {
304         int rv;
305
306 #ifndef DISABLE_IPV6
307         if (h->family == FW3_FAMILY_V6)
308         {
309                 rv = ip6tc_commit(h->handle);
310                 if (!rv)
311                         warn("ip6tc_commit(): %s", ip6tc_strerror(errno));
312         }
313         else
314 #endif
315         {
316                 rv = iptc_commit(h->handle);
317                 if (!rv)
318                         warn("iptc_commit(): %s", iptc_strerror(errno));
319         }
320 }
321
322 void
323 fw3_ipt_close(struct fw3_ipt_handle *h)
324 {
325         if (h->libv)
326         {
327                 while (h->libc > 0)
328                 {
329                         h->libc--;
330                         dlclose(h->libv[h->libc]);
331                 }
332
333                 free(h->libv);
334         }
335
336         free(h);
337 }
338
339 struct fw3_ipt_rule *
340 fw3_ipt_rule_new(struct fw3_ipt_handle *h)
341 {
342         struct fw3_ipt_rule *r;
343
344         r = fw3_alloc(sizeof(*r));
345
346         r->h = h;
347         r->argv = fw3_alloc(sizeof(char *));
348         r->argv[r->argc++] = "fw3";
349
350         return r;
351 }
352
353
354 static bool
355 is_chain(struct fw3_ipt_handle *h, const char *name)
356 {
357 #ifndef DISABLE_IPV6
358         if (h->family == FW3_FAMILY_V6)
359                 return ip6tc_is_chain(name, h->handle);
360         else
361 #endif
362                 return iptc_is_chain(name, h->handle);
363 }
364
365 static char *
366 get_protoname(struct fw3_ipt_rule *r)
367 {
368         const struct xtables_pprot *pp;
369
370         if (r->protocol)
371                 for (pp = xtables_chain_protos; pp->name; pp++)
372                         if (pp->num == r->protocol)
373                                 return (char *)pp->name;
374
375         return NULL;
376 }
377
378 static bool
379 load_extension(struct fw3_ipt_handle *h, const char *name)
380 {
381         char path[256];
382         void *lib, **tmp;
383         const char *pfx = (h->family == FW3_FAMILY_V6) ? "libip6t" : "libipt";
384
385         snprintf(path, sizeof(path), "/usr/lib/iptables/libxt_%s.so", name);
386         if (!(lib = dlopen(path, RTLD_NOW)))
387         {
388                 snprintf(path, sizeof(path), "/usr/lib/iptables/%s_%s.so", pfx, name);
389                 lib = dlopen(path, RTLD_NOW);
390         }
391
392         if (!lib)
393                 return false;
394
395         tmp = realloc(h->libv, sizeof(lib) * (h->libc + 1));
396
397         if (!tmp)
398                 return false;
399
400         h->libv = tmp;
401         h->libv[h->libc++] = lib;
402
403         return true;
404 }
405
406 static struct xtables_match *
407 find_match(struct fw3_ipt_rule *r, const char *name)
408 {
409         struct xtables_match *m;
410
411         m = xtables_find_match(name, XTF_DONT_LOAD, &r->matches);
412
413         if (!m && load_extension(r->h, name))
414                 m = xtables_find_match(name, XTF_DONT_LOAD, &r->matches);
415
416         return m;
417 }
418
419 static void
420 init_match(struct fw3_ipt_rule *r, struct xtables_match *m, bool no_clone)
421 {
422         size_t s;
423         struct xtables_globals *g;
424
425         if (!m)
426                 return;
427
428         s = XT_ALIGN(sizeof(struct xt_entry_match)) + m->size;
429
430         m->m = fw3_alloc(s);
431
432         fw3_xt_set_match_name(m);
433
434         m->m->u.user.revision = m->revision;
435         m->m->u.match_size = s;
436
437         /* free previous userspace data */
438         fw3_xt_free_match_udata(m);
439
440         if (m->init)
441                 m->init(m->m);
442
443         /* don't merge options if no_clone is set and this match is a clone */
444         if (no_clone && (m == m->next))
445                 return;
446
447         /* merge option table */
448         g = (r->h->family == FW3_FAMILY_V6) ? &xtg6 : &xtg;
449         fw3_xt_merge_match_options(g, m);
450 }
451
452 static bool
453 need_protomatch(struct fw3_ipt_rule *r, const char *pname)
454 {
455         if (!pname)
456                 return false;
457
458         if (!xtables_find_match(pname, XTF_DONT_LOAD, NULL))
459                 return true;
460
461         return !r->protocol_loaded;
462 }
463
464 static struct xtables_match *
465 load_protomatch(struct fw3_ipt_rule *r)
466 {
467         const char *pname = get_protoname(r);
468
469         if (!need_protomatch(r, pname))
470                 return NULL;
471
472         return find_match(r, pname);
473 }
474
475 static struct xtables_target *
476 find_target(struct fw3_ipt_rule *r, const char *name)
477 {
478         struct xtables_target *t;
479
480         if (is_chain(r->h, name))
481                 return xtables_find_target(XT_STANDARD_TARGET, XTF_LOAD_MUST_SUCCEED);
482
483         t = xtables_find_target(name, XTF_DONT_LOAD);
484
485         if (!t && load_extension(r->h, name))
486                 t = xtables_find_target(name, XTF_DONT_LOAD);
487
488         return t;
489 }
490
491 static struct xtables_target *
492 get_target(struct fw3_ipt_rule *r, const char *name)
493 {
494         size_t s;
495         struct xtables_target *t;
496         struct xtables_globals *g;
497
498         t = find_target(r, name);
499
500         if (!t)
501                 return NULL;
502
503         s = XT_ALIGN(sizeof(struct xt_entry_target)) + t->size;
504         t->t = fw3_alloc(s);
505
506         fw3_xt_set_target_name(t, name);
507
508         t->t->u.user.revision = t->revision;
509         t->t->u.target_size = s;
510
511         /* free previous userspace data */
512         fw3_xt_free_target_udata(t);
513
514         if (t->init)
515                 t->init(t->t);
516
517         /* merge option table */
518         g = (r->h->family == FW3_FAMILY_V6) ? &xtg6 : &xtg;
519         fw3_xt_merge_target_options(g, t);
520
521         r->target = t;
522
523         return t;
524 }
525
526 void
527 fw3_ipt_rule_proto(struct fw3_ipt_rule *r, struct fw3_protocol *proto)
528 {
529         uint32_t pr;
530
531         if (!proto || proto->any)
532                 return;
533
534         pr = proto->protocol;
535
536 #ifndef DISABLE_IPV6
537         if (r->h->family == FW3_FAMILY_V6)
538         {
539                 if (pr == 1)
540                         pr = 58;
541
542                 r->e6.ipv6.proto = pr;
543                 r->e6.ipv6.flags |= IP6T_F_PROTO;
544
545                 if (proto->invert)
546                         r->e6.ipv6.invflags |= XT_INV_PROTO;
547         }
548         else
549 #endif
550         {
551                 r->e.ip.proto = pr;
552
553                 if (proto->invert)
554                         r->e.ip.invflags |= XT_INV_PROTO;
555         }
556
557         r->protocol = pr;
558 }
559
560 void
561 fw3_ipt_rule_in_out(struct fw3_ipt_rule *r,
562                     struct fw3_device *in, struct fw3_device *out)
563 {
564 #ifndef DISABLE_IPV6
565         if (r->h->family == FW3_FAMILY_V6)
566         {
567                 if (in && !in->any)
568                 {
569                         xtables_parse_interface(in->name, r->e6.ipv6.iniface,
570                                                           r->e6.ipv6.iniface_mask);
571
572                         if (in->invert)
573                                 r->e6.ipv6.invflags |= IP6T_INV_VIA_IN;
574                 }
575
576                 if (out && !out->any)
577                 {
578                         xtables_parse_interface(out->name, r->e6.ipv6.outiface,
579                                                            r->e6.ipv6.outiface_mask);
580
581                         if (out->invert)
582                                 r->e6.ipv6.invflags |= IP6T_INV_VIA_OUT;
583                 }
584         }
585         else
586 #endif
587         {
588                 if (in && !in->any)
589                 {
590                         xtables_parse_interface(in->name, r->e.ip.iniface,
591                                                           r->e.ip.iniface_mask);
592
593                         if (in->invert)
594                                 r->e.ip.invflags |= IPT_INV_VIA_IN;
595                 }
596
597                 if (out && !out->any)
598                 {
599                         xtables_parse_interface(out->name, r->e.ip.outiface,
600                                                            r->e.ip.outiface_mask);
601
602                         if (out->invert)
603                                 r->e.ip.invflags |= IPT_INV_VIA_OUT;
604                 }
605         }
606 }
607
608
609 static void
610 ip4prefix2mask(int prefix, struct in_addr *mask)
611 {
612         if (prefix > 0)
613                 mask->s_addr = htonl(~((1 << (32 - prefix)) - 1));
614         else
615                 mask->s_addr = 0;
616 }
617
618 #ifndef DISABLE_IPV6
619 static void
620 ip6prefix2mask(int prefix, struct in6_addr *mask)
621 {
622         char *p = (char *)mask;
623
624         if (prefix > 0)
625         {
626                 memset(p, 0xff, prefix / 8);
627                 memset(p + (prefix / 8) + 1, 0, (128 - prefix) / 8);
628                 p[prefix / 8] = 0xff << (8 - (prefix & 7));
629         }
630         else
631         {
632                 memset(mask, 0, sizeof(*mask));
633         }
634 }
635 #endif
636
637 void
638 fw3_ipt_rule_src_dest(struct fw3_ipt_rule *r,
639                       struct fw3_address *src, struct fw3_address *dest)
640 {
641         if ((src && src->range) || (dest && dest->range))
642         {
643                 fw3_ipt_rule_addarg(r, false, "-m", "iprange");
644         }
645
646         if (src && src->set)
647         {
648                 if (src->range)
649                 {
650                         fw3_ipt_rule_addarg(r, src->invert, "--src-range",
651                                             fw3_address_to_string(src, false));
652                 }
653 #ifndef DISABLE_IPV6
654                 else if (r->h->family == FW3_FAMILY_V6)
655                 {
656                         r->e6.ipv6.src = src->address.v6;
657                         ip6prefix2mask(src->mask, &r->e6.ipv6.smsk);
658
659                         int i;
660                         for (i = 0; i < 4; i++)
661                                 r->e6.ipv6.src.s6_addr32[i] &= r->e6.ipv6.smsk.s6_addr32[i];
662
663                         if (src->invert)
664                                 r->e6.ipv6.invflags |= IP6T_INV_SRCIP;
665                 }
666 #endif
667                 else
668                 {
669                         r->e.ip.src = src->address.v4;
670                         ip4prefix2mask(src->mask, &r->e.ip.smsk);
671
672                         r->e.ip.src.s_addr &= r->e.ip.smsk.s_addr;
673
674                         if (src->invert)
675                                 r->e.ip.invflags |= IPT_INV_SRCIP;
676                 }
677         }
678
679         if (dest && dest->set)
680         {
681                 if (dest->range)
682                 {
683                         fw3_ipt_rule_addarg(r, dest->invert, "--dst-range",
684                                             fw3_address_to_string(dest, false));
685                 }
686 #ifndef DISABLE_IPV6
687                 else if (r->h->family == FW3_FAMILY_V6)
688                 {
689                         r->e6.ipv6.dst = dest->address.v6;
690                         ip6prefix2mask(dest->mask, &r->e6.ipv6.dmsk);
691
692                         int i;
693                         for (i = 0; i < 4; i++)
694                                 r->e6.ipv6.dst.s6_addr32[i] &= r->e6.ipv6.dmsk.s6_addr32[i];
695
696                         if (dest->invert)
697                                 r->e6.ipv6.invflags |= IP6T_INV_DSTIP;
698                 }
699 #endif
700                 else
701                 {
702                         r->e.ip.dst = dest->address.v4;
703                         ip4prefix2mask(dest->mask, &r->e.ip.dmsk);
704
705                         r->e.ip.dst.s_addr &= r->e.ip.dmsk.s_addr;
706
707                         if (dest->invert)
708                                 r->e.ip.invflags |= IPT_INV_DSTIP;
709                 }
710         }
711 }
712
713 void
714 fw3_ipt_rule_sport_dport(struct fw3_ipt_rule *r,
715                          struct fw3_port *sp, struct fw3_port *dp)
716 {
717         char buf[sizeof("65535:65535\0")];
718
719         if ((!sp || !sp->set) && (!dp || !dp->set))
720                 return;
721
722         if (!get_protoname(r))
723                 return;
724
725         if (sp && sp->set)
726         {
727                 if (sp->port_min == sp->port_max)
728                         sprintf(buf, "%u", sp->port_min);
729                 else
730                         sprintf(buf, "%u:%u", sp->port_min, sp->port_max);
731
732                 fw3_ipt_rule_addarg(r, sp->invert, "--sport", buf);
733         }
734
735         if (dp && dp->set)
736         {
737                 if (dp->port_min == dp->port_max)
738                         sprintf(buf, "%u", dp->port_min);
739                 else
740                         sprintf(buf, "%u:%u", dp->port_min, dp->port_max);
741
742                 fw3_ipt_rule_addarg(r, dp->invert, "--dport", buf);
743         }
744 }
745
746 void
747 fw3_ipt_rule_mac(struct fw3_ipt_rule *r, struct fw3_mac *mac)
748 {
749         char buf[sizeof("ff:ff:ff:ff:ff:ff\0")];
750         uint8_t *addr = mac->mac.ether_addr_octet;
751
752         if (!mac)
753                 return;
754
755         sprintf(buf, "%02x:%02x:%02x:%02x:%02x:%02x",
756                 addr[0], addr[1], addr[2], addr[3], addr[4], addr[5]);
757
758         fw3_ipt_rule_addarg(r, false, "-m", "mac");
759         fw3_ipt_rule_addarg(r, mac->invert, "--mac-source", buf);
760 }
761
762 void
763 fw3_ipt_rule_icmptype(struct fw3_ipt_rule *r, struct fw3_icmptype *icmp)
764 {
765         char buf[sizeof("255/255\0")];
766
767         if (!icmp)
768                 return;
769
770 #ifndef DISABLE_IPV6
771         if (r->h->family == FW3_FAMILY_V6)
772         {
773                 if (icmp->code6_min == 0 && icmp->code6_max == 0xFF)
774                         sprintf(buf, "%u", icmp->type6);
775                 else
776                         sprintf(buf, "%u/%u", icmp->type6, icmp->code6_min);
777
778                 fw3_ipt_rule_addarg(r, icmp->invert, "--icmpv6-type", buf);
779         }
780         else
781 #endif
782         {
783                 if (icmp->code_min == 0 && icmp->code_max == 0xFF)
784                         sprintf(buf, "%u", icmp->type);
785                 else
786                         sprintf(buf, "%u/%u", icmp->type, icmp->code_min);
787
788                 fw3_ipt_rule_addarg(r, icmp->invert, "--icmp-type", buf);
789         }
790 }
791
792 void
793 fw3_ipt_rule_limit(struct fw3_ipt_rule *r, struct fw3_limit *limit)
794 {
795         char buf[sizeof("-4294967296/second\0")];
796
797         if (!limit || limit->rate <= 0)
798                 return;
799
800         fw3_ipt_rule_addarg(r, false, "-m", "limit");
801
802         sprintf(buf, "%u/%s", limit->rate, fw3_limit_units[limit->unit]);
803         fw3_ipt_rule_addarg(r, limit->invert, "--limit", buf);
804
805         if (limit->burst > 0)
806         {
807                 sprintf(buf, "%u", limit->burst);
808                 fw3_ipt_rule_addarg(r, limit->invert, "--limit-burst", buf);
809         }
810 }
811
812 void
813 fw3_ipt_rule_ipset(struct fw3_ipt_rule *r, struct fw3_setmatch *match)
814 {
815         char buf[sizeof("dst,dst,dst\0")];
816         char *p = buf;
817         int i = 0;
818
819         struct fw3_ipset *set;
820         struct fw3_ipset_datatype *type;
821
822         if (!match || !match->set || !match->ptr)
823                 return;
824
825         set = match->ptr;
826         list_for_each_entry(type, &set->datatypes, list)
827         {
828                 if (i >= 3)
829                         break;
830
831                 if (p > buf)
832                         *p++ = ',';
833
834                 p += sprintf(p, "%s", match->dir[i] ? match->dir[i] : type->dir);
835                 i++;
836         }
837
838         fw3_ipt_rule_addarg(r, false, "-m", "set");
839
840         fw3_ipt_rule_addarg(r, match->invert, "--match-set",
841                             set->external ? set->external : set->name);
842
843         fw3_ipt_rule_addarg(r, false, buf, NULL);
844 }
845
846 void
847 fw3_ipt_rule_time(struct fw3_ipt_rule *r, struct fw3_time *time)
848 {
849         int i;
850         struct tm empty = { 0 };
851
852         char buf[84]; /* sizeof("1,2,3,...,30,31\0") */
853         char *p;
854
855         bool d1 = memcmp(&time->datestart, &empty, sizeof(empty));
856         bool d2 = memcmp(&time->datestop, &empty, sizeof(empty));
857
858         if (!d1 && !d2 && !time->timestart && !time->timestop &&
859             !(time->monthdays & 0xFFFFFFFE) && !(time->weekdays & 0xFE))
860         {
861                 return;
862         }
863
864         fw3_ipt_rule_addarg(r, false, "-m", "time");
865
866         if (time->utc)
867                 fw3_ipt_rule_addarg(r, false, "--utc", NULL);
868
869         if (d1)
870         {
871                 strftime(buf, sizeof(buf), "%Y-%m-%dT%H:%M:%S", &time->datestart);
872                 fw3_ipt_rule_addarg(r, false, "--datestart", buf);
873         }
874
875         if (d2)
876         {
877                 strftime(buf, sizeof(buf), "%Y-%m-%dT%H:%M:%S", &time->datestop);
878                 fw3_ipt_rule_addarg(r, false, "--datestop", buf);
879         }
880
881         if (time->timestart)
882         {
883                 sprintf(buf, "%02d:%02d:%02d",
884                         time->timestart / 3600,
885                         time->timestart % 3600 / 60,
886                         time->timestart % 60);
887
888                 fw3_ipt_rule_addarg(r, false, "--timestart", buf);
889         }
890
891         if (time->timestop)
892         {
893                 sprintf(buf, "%02d:%02d:%02d",
894                         time->timestop / 3600,
895                         time->timestop % 3600 / 60,
896                         time->timestop % 60);
897
898                 fw3_ipt_rule_addarg(r, false, "--timestop", buf);
899         }
900
901         if (time->monthdays & 0xFFFFFFFE)
902         {
903                 for (i = 1, p = buf; i < 32; i++)
904                 {
905                         if (hasbit(time->monthdays, i))
906                         {
907                                 if (p > buf)
908                                         *p++ = ',';
909
910                                 p += sprintf(p, "%u", i);
911                         }
912                 }
913
914                 fw3_ipt_rule_addarg(r, hasbit(time->monthdays, 0), "--monthdays", buf);
915         }
916
917         if (time->weekdays & 0xFE)
918         {
919                 for (i = 1, p = buf; i < 8; i++)
920                 {
921                         if (hasbit(time->weekdays, i))
922                         {
923                                 if (p > buf)
924                                         *p++ = ',';
925
926                                 p += sprintf(p, "%u", i);
927                         }
928                 }
929
930                 fw3_ipt_rule_addarg(r, hasbit(time->weekdays, 0), "--weekdays", buf);
931         }
932 }
933
934 void
935 fw3_ipt_rule_mark(struct fw3_ipt_rule *r, struct fw3_mark *mark)
936 {
937         char buf[sizeof("0xFFFFFFFF/0xFFFFFFFF\0")];
938
939         if (!mark || !mark->set)
940                 return;
941
942         if (mark->mask < 0xFFFFFFFF)
943                 sprintf(buf, "0x%x/0x%x", mark->mark, mark->mask);
944         else
945                 sprintf(buf, "0x%x", mark->mark);
946
947         fw3_ipt_rule_addarg(r, false, "-m", "mark");
948         fw3_ipt_rule_addarg(r, mark->invert, "--mark", buf);
949 }
950
951 void
952 fw3_ipt_rule_comment(struct fw3_ipt_rule *r, const char *fmt, ...)
953 {
954         va_list ap;
955         char buf[256];
956
957         if (!fmt || !*fmt)
958                 return;
959
960         va_start(ap, fmt);
961         vsnprintf(buf, sizeof(buf) - 1, fmt, ap);
962         va_end(ap);
963
964         fw3_ipt_rule_addarg(r, false, "-m", "comment");
965         fw3_ipt_rule_addarg(r, false, "--comment", buf);
966 }
967
968 void
969 fw3_ipt_rule_extra(struct fw3_ipt_rule *r, const char *extra)
970 {
971         char *p, **tmp, *s;
972
973         if (!extra || !*extra)
974                 return;
975
976         s = fw3_strdup(extra);
977
978         for (p = strtok(s, " \t"); p; p = strtok(NULL, " \t"))
979         {
980                 tmp = realloc(r->argv, (r->argc + 1) * sizeof(*r->argv));
981
982                 if (!tmp)
983                         break;
984
985                 r->argv = tmp;
986                 r->argv[r->argc++] = fw3_strdup(p);
987         }
988
989         free(s);
990 }
991
992 #ifndef DISABLE_IPV6
993 static void
994 rule_print6(struct ip6t_entry *e)
995 {
996         char buf[INET6_ADDRSTRLEN];
997         char *pname;
998
999         if (e->ipv6.flags & IP6T_F_PROTO)
1000         {
1001                 if (e->ipv6.flags & XT_INV_PROTO)
1002                         printf(" !");
1003
1004                 pname = get_protoname(container_of(e, struct fw3_ipt_rule, e6));
1005
1006                 if (pname)
1007                         printf(" -p %s", pname);
1008                 else
1009                         printf(" -p %u", e->ipv6.proto);
1010         }
1011
1012         if (e->ipv6.iniface[0])
1013         {
1014                 if (e->ipv6.flags & IP6T_INV_VIA_IN)
1015                         printf(" !");
1016
1017                 printf(" -i %s", e->ipv6.iniface);
1018         }
1019
1020         if (e->ipv6.outiface[0])
1021         {
1022                 if (e->ipv6.flags & IP6T_INV_VIA_OUT)
1023                         printf(" !");
1024
1025                 printf(" -o %s", e->ipv6.outiface);
1026         }
1027
1028         if (memcmp(&e->ipv6.src, &in6addr_any, sizeof(struct in6_addr)))
1029         {
1030                 if (e->ipv6.flags & IP6T_INV_SRCIP)
1031                         printf(" !");
1032
1033                 printf(" -s %s/%u", inet_ntop(AF_INET6, &e->ipv6.src, buf, sizeof(buf)),
1034                                     xtables_ip6mask_to_cidr(&e->ipv6.smsk));
1035         }
1036
1037         if (memcmp(&e->ipv6.dst, &in6addr_any, sizeof(struct in6_addr)))
1038         {
1039                 if (e->ipv6.flags & IP6T_INV_DSTIP)
1040                         printf(" !");
1041
1042                 printf(" -d %s/%u", inet_ntop(AF_INET6, &e->ipv6.dst, buf, sizeof(buf)),
1043                                     xtables_ip6mask_to_cidr(&e->ipv6.dmsk));
1044         }
1045 }
1046 #endif
1047
1048 static void
1049 rule_print4(struct ipt_entry *e)
1050 {
1051         struct in_addr in_zero = { 0 };
1052         char buf[sizeof("255.255.255.255\0")];
1053         char *pname;
1054
1055         if (e->ip.proto)
1056         {
1057                 if (e->ip.flags & XT_INV_PROTO)
1058                         printf(" !");
1059
1060                 pname = get_protoname(container_of(e, struct fw3_ipt_rule, e));
1061
1062                 if (pname)
1063                         printf(" -p %s", pname);
1064                 else
1065                         printf(" -p %u", e->ip.proto);
1066         }
1067
1068         if (e->ip.iniface[0])
1069         {
1070                 if (e->ip.flags & IPT_INV_VIA_IN)
1071                         printf(" !");
1072
1073                 printf(" -i %s", e->ip.iniface);
1074         }
1075
1076         if (e->ip.outiface[0])
1077         {
1078                 if (e->ip.flags & IPT_INV_VIA_OUT)
1079                         printf(" !");
1080
1081                 printf(" -o %s", e->ip.outiface);
1082         }
1083
1084         if (memcmp(&e->ip.src, &in_zero, sizeof(struct in_addr)))
1085         {
1086                 if (e->ip.flags & IPT_INV_SRCIP)
1087                         printf(" !");
1088
1089                 printf(" -s %s/%u", inet_ntop(AF_INET, &e->ip.src, buf, sizeof(buf)),
1090                                     xtables_ipmask_to_cidr(&e->ip.smsk));
1091         }
1092
1093         if (memcmp(&e->ip.dst, &in_zero, sizeof(struct in_addr)))
1094         {
1095                 if (e->ip.flags & IPT_INV_DSTIP)
1096                         printf(" !");
1097
1098                 printf(" -d %s/%u", inet_ntop(AF_INET, &e->ip.dst, buf, sizeof(buf)),
1099                                     xtables_ipmask_to_cidr(&e->ip.dmsk));
1100         }
1101 }
1102
1103 static void
1104 rule_print(struct fw3_ipt_rule *r, const char *prefix, const char *chain)
1105 {
1106         debug(r->h, "%s %s", prefix, chain);
1107
1108 #ifndef DISABLE_IPV6
1109         if (r->h->family == FW3_FAMILY_V6)
1110                 rule_print6(&r->e6);
1111         else
1112 #endif
1113                 rule_print4(&r->e);
1114
1115         fw3_xt_print_matches(&r->e.ip, r->matches);
1116         fw3_xt_print_target(&r->e.ip, r->target);
1117
1118         printf("\n");
1119 }
1120
1121 static bool
1122 parse_option(struct fw3_ipt_rule *r, int optc, bool inv)
1123 {
1124         struct xtables_rule_match *m;
1125         struct xtables_match *em;
1126
1127         /* is a target option */
1128         if (r->target && fw3_xt_has_target_parse(r->target) &&
1129                 optc >= r->target->option_offset &&
1130                 optc < (r->target->option_offset + 256))
1131         {
1132                 xtables_option_tpcall(optc, r->argv, inv, r->target, &r->e);
1133                 return false;
1134         }
1135
1136         /* try to dispatch argument to one of the match parsers */
1137         for (m = r->matches; m; m = m->next)
1138         {
1139                 em = m->match;
1140
1141                 if (m->completed || !fw3_xt_has_match_parse(em))
1142                         continue;
1143
1144                 if (optc < em->option_offset ||
1145                         optc >= (em->option_offset + 256))
1146                         continue;
1147
1148                 xtables_option_mpcall(optc, r->argv, inv, em, &r->e);
1149                 return false;
1150         }
1151
1152         /* unhandled option, might belong to a protocol match */
1153         if ((em = load_protomatch(r)) != NULL)
1154         {
1155                 init_match(r, em, false);
1156
1157                 r->protocol_loaded = true;
1158                 optind--;
1159
1160                 return true;
1161         }
1162
1163         if (optc == ':')
1164                 warn("parse_option(): option '%s' needs argument", r->argv[optind-1]);
1165
1166         if (optc == '?')
1167                 warn("parse_option(): unknown option '%s'", r->argv[optind-1]);
1168
1169         return false;
1170 }
1171
1172 void
1173 fw3_ipt_rule_addarg(struct fw3_ipt_rule *r, bool inv,
1174                     const char *k, const char *v)
1175 {
1176         int n;
1177         char **tmp;
1178
1179         if (!k)
1180                 return;
1181
1182         n = inv + !!k + !!v;
1183         tmp = realloc(r->argv, (r->argc + n) * sizeof(*tmp));
1184
1185         if (!tmp)
1186                 return;
1187
1188         r->argv = tmp;
1189
1190         if (inv)
1191                 r->argv[r->argc++] = fw3_strdup("!");
1192
1193         r->argv[r->argc++] = fw3_strdup(k);
1194
1195         if (v)
1196                 r->argv[r->argc++] = fw3_strdup(v);
1197 }
1198
1199 static unsigned char *
1200 rule_mask(struct fw3_ipt_rule *r)
1201 {
1202         size_t s;
1203         unsigned char *p, *mask = NULL;
1204         struct xtables_rule_match *m;
1205
1206 #define SZ(x) XT_ALIGN(sizeof(struct x))
1207
1208 #ifndef DISABLE_IPV6
1209         if (r->h->family == FW3_FAMILY_V6)
1210         {
1211                 s = SZ(ip6t_entry);
1212
1213                 for (m = r->matches; m; m = m->next)
1214                         s += SZ(ip6t_entry_match) + m->match->size;
1215
1216                 s += SZ(ip6t_entry_target) + r->target->size;
1217
1218                 mask = fw3_alloc(s);
1219                 memset(mask, 0xFF, SZ(ip6t_entry));
1220                 p = mask + SZ(ip6t_entry);
1221
1222                 for (m = r->matches; m; m = m->next)
1223                 {
1224                         memset(p, 0xFF, SZ(ip6t_entry_match) + m->match->userspacesize);
1225                         p += SZ(ip6t_entry_match) + m->match->size;
1226                 }
1227
1228                 memset(p, 0xFF, SZ(ip6t_entry_target) + r->target->userspacesize);
1229         }
1230         else
1231 #endif
1232         {
1233                 s = SZ(ipt_entry);
1234
1235                 for (m = r->matches; m; m = m->next)
1236                         s += SZ(ipt_entry_match) + m->match->size;
1237
1238                 s += SZ(ipt_entry_target) + r->target->size;
1239
1240                 mask = fw3_alloc(s);
1241                 memset(mask, 0xFF, SZ(ipt_entry));
1242                 p = mask + SZ(ipt_entry);
1243
1244                 for (m = r->matches; m; m = m->next)
1245                 {
1246                         memset(p, 0xFF, SZ(ipt_entry_match) + m->match->userspacesize);
1247                         p += SZ(ipt_entry_match) + m->match->size;
1248                 }
1249
1250                 memset(p, 0xFF, SZ(ipt_entry_target) + r->target->userspacesize);
1251         }
1252
1253         return mask;
1254 }
1255
1256 static void *
1257 rule_build(struct fw3_ipt_rule *r)
1258 {
1259         size_t s;
1260         struct xtables_rule_match *m;
1261
1262 #ifndef DISABLE_IPV6
1263         if (r->h->family == FW3_FAMILY_V6)
1264         {
1265                 struct ip6t_entry *e6;
1266
1267                 s = XT_ALIGN(sizeof(struct ip6t_entry));
1268
1269                 for (m = r->matches; m; m = m->next)
1270                         s += m->match->m->u.match_size;
1271
1272                 e6 = fw3_alloc(s + r->target->t->u.target_size);
1273
1274                 memcpy(e6, &r->e6, sizeof(struct ip6t_entry));
1275
1276                 e6->target_offset = s;
1277                 e6->next_offset = s + r->target->t->u.target_size;
1278
1279                 s = 0;
1280
1281                 for (m = r->matches; m; m = m->next)
1282                 {
1283                         memcpy(e6->elems + s, m->match->m, m->match->m->u.match_size);
1284                         s += m->match->m->u.match_size;
1285                 }
1286
1287                 memcpy(e6->elems + s, r->target->t, r->target->t->u.target_size);
1288
1289                 return e6;
1290         }
1291         else
1292 #endif
1293         {
1294                 struct ipt_entry *e;
1295
1296                 s = XT_ALIGN(sizeof(struct ipt_entry));
1297
1298                 for (m = r->matches; m; m = m->next)
1299                         s += m->match->m->u.match_size;
1300
1301                 e = fw3_alloc(s + r->target->t->u.target_size);
1302
1303                 memcpy(e, &r->e, sizeof(struct ipt_entry));
1304
1305                 e->target_offset = s;
1306                 e->next_offset = s + r->target->t->u.target_size;
1307
1308                 s = 0;
1309
1310                 for (m = r->matches; m; m = m->next)
1311                 {
1312                         memcpy(e->elems + s, m->match->m, m->match->m->u.match_size);
1313                         s += m->match->m->u.match_size;
1314                 }
1315
1316                 memcpy(e->elems + s, r->target->t, r->target->t->u.target_size);
1317
1318                 return e;
1319         }
1320 }
1321
1322 void
1323 __fw3_ipt_rule_append(struct fw3_ipt_rule *r, bool repl, const char *fmt, ...)
1324 {
1325         void *rule;
1326         unsigned char *mask;
1327
1328         struct xtables_rule_match *m;
1329         struct xtables_match *em;
1330         struct xtables_target *et;
1331         struct xtables_globals *g;
1332
1333         int i, optc;
1334         bool inv = false;
1335         char buf[32];
1336         va_list ap;
1337
1338         va_start(ap, fmt);
1339         vsnprintf(buf, sizeof(buf) - 1, fmt, ap);
1340         va_end(ap);
1341
1342         g = (r->h->family == FW3_FAMILY_V6) ? &xtg6 : &xtg;
1343         g->opts = g->orig_opts;
1344
1345         optind = 0;
1346         opterr = 0;
1347
1348         while ((optc = getopt_long(r->argc, r->argv, "-:m:j:", g->opts,
1349                                    NULL)) != -1)
1350         {
1351                 switch (optc)
1352                 {
1353                 case 'm':
1354                         em = find_match(r, optarg);
1355
1356                         if (!em)
1357                         {
1358                                 warn("fw3_ipt_rule_append(): Can't find match '%s'", optarg);
1359                                 goto free;
1360                         }
1361
1362                         init_match(r, em, true);
1363                         break;
1364
1365                 case 'j':
1366                         et = get_target(r, optarg);
1367
1368                         if (!et)
1369                         {
1370                                 warn("fw3_ipt_rule_append(): Can't find target '%s'", optarg);
1371                                 goto free;
1372                         }
1373
1374                         break;
1375
1376                 case 1:
1377                         if ((optarg[0] == '!') && (optarg[1] == '\0'))
1378                         {
1379                                 optarg[0] = '\0';
1380                                 inv = true;
1381                                 continue;
1382                         }
1383
1384                         warn("fw3_ipt_rule_append(): Bad argument '%s'", optarg);
1385                         goto free;
1386
1387                 default:
1388                         if (parse_option(r, optc, inv))
1389                                 continue;
1390                         break;
1391                 }
1392
1393                 inv = false;
1394         }
1395
1396         for (m = r->matches; m; m = m->next)
1397                 xtables_option_mfcall(m->match);
1398
1399         if (r->target)
1400                 xtables_option_tfcall(r->target);
1401
1402         rule = rule_build(r);
1403
1404 #ifndef DISABLE_IPV6
1405         if (r->h->family == FW3_FAMILY_V6)
1406         {
1407                 if (repl)
1408                 {
1409                         mask = rule_mask(r);
1410
1411                         while (ip6tc_delete_entry(buf, rule, mask, r->h->handle))
1412                                 if (fw3_pr_debug)
1413                                         rule_print(r, "-D", buf);
1414
1415                         free(mask);
1416                 }
1417
1418                 if (fw3_pr_debug)
1419                         rule_print(r, "-A", buf);
1420
1421                 if (!ip6tc_append_entry(buf, rule, r->h->handle))
1422                         warn("ip6tc_append_entry(): %s", ip6tc_strerror(errno));
1423         }
1424         else
1425 #endif
1426         {
1427                 if (repl)
1428                 {
1429                         mask = rule_mask(r);
1430
1431                         while (iptc_delete_entry(buf, rule, mask, r->h->handle))
1432                                 if (fw3_pr_debug)
1433                                         rule_print(r, "-D", buf);
1434
1435                         free(mask);
1436                 }
1437
1438                 if (fw3_pr_debug)
1439                         rule_print(r, "-A", buf);
1440
1441                 if (!iptc_append_entry(buf, rule, r->h->handle))
1442                         warn("iptc_append_entry(): %s\n", iptc_strerror(errno));
1443         }
1444
1445         free(rule);
1446
1447 free:
1448         for (i = 1; i < r->argc; i++)
1449                 free(r->argv[i]);
1450
1451         free(r->argv);
1452
1453         xtables_rule_matches_free(&r->matches);
1454
1455         if (r->target)
1456                 free(r->target->t);
1457
1458         free(r);
1459
1460         /* reset all targets and matches */
1461         for (em = xtables_matches; em; em = em->next)
1462                 em->mflags = 0;
1463
1464         for (et = xtables_targets; et; et = et->next)
1465         {
1466                 et->tflags = 0;
1467                 et->used = 0;
1468         }
1469
1470         xtables_free_opts(1);
1471 }
1472
1473 struct fw3_ipt_rule *
1474 fw3_ipt_rule_create(struct fw3_ipt_handle *handle, struct fw3_protocol *proto,
1475                     struct fw3_device *in, struct fw3_device *out,
1476                     struct fw3_address *src, struct fw3_address *dest)
1477 {
1478         struct fw3_ipt_rule *r;
1479
1480         r = fw3_ipt_rule_new(handle);
1481
1482         fw3_ipt_rule_proto(r, proto);
1483         fw3_ipt_rule_in_out(r, in, out);
1484         fw3_ipt_rule_src_dest(r, src, dest);
1485
1486         return r;
1487 }